Methods of treating psychiatric disorders in obese patients with brexpiprazole

ABSTRACT

The present disclosure relates to methods of initiating brexpiprazole treating in patients with schizophrenia or major depressive disorder. The present disclosure further relates to modified dosing regimens for obese patients and/or patients that are CYP2D6 poor metabolizers. In embodiments, the modified dosing regimens administers double the daily dose while initiating treatment.

BACKGROUND

Brexpiprazole, also called REXULTI®, is an atypical antipsychotic usedfor treating major depressive disorder and schizophrenia. The mechanismof action of brexpiprazole in the treatment of major depressive disorder(MDD) and schizophrenia is unknown. However, the efficacy ofbrexpiprazole may result from partial agonist activity at serotonin5-HT_(1A) and dopamine D2 receptors and antagonist activity at serotonin5-HT_(2A) receptors.

The brexpiprazole (REXULTI®) Food and Drug Administration (FDA) labelrevised in March 2020 reflects the state-of-the art regarding theappropriate dosing for patients in need of brexpiprazole, and providesinstructions for a brexpiprazole starting dose, recommended dose, andmaximum dose with a titration timeline based on a patient's clinicalresponse and tolerability. The FDA label also provides instructions toadminister half of the usual dose to patients that are CYP2D6 poormetabolizers.

An ideal dosage regimen for brexpiprazole enables psychiatric patientsto reach therapeutic levels of brexpiprazole as quickly as possiblewhile avoiding side effects from brexpiprazole. One serious side effectof administering too much brexpiprazole is akathisia, a movement andmental distress disorder which is a state of agitation, distress, andrestlessness. Akathisia rates in brexpiprazole patients have been shownto be dose-dependent, and increase as exposure to brexpiprazoleincreases.

It is not presently recognized in the art that the dosing regimen forbrexpiprazole should be adjusted based on the body weight or obesitystatus of the patient, despite the fact that obesity and schizophreniaor depression are often comorbid conditions. While the REXULTI® label,for example, teaches that weight gain can be a side effect of treatmentwith brexpiprazole, or that being overweight is a risk factor for otherside effects such as hyperglycemia, the label does not instruct anychanges in dosing for obese or overweight patients compared to normalweight patients. Brexpiprazole dosing adjustments are only recommendedbased on the indication treated, hepatic or renal impairment status,drug interactions with CYP2D6 inhibitors, or CYP3A4 inhibitors orinducers.

SUMMARY OF THE INVENTION

The inventors have discovered that the pharmacokinetics of brexpiprazoleare substantively different in obese patients, requiring dosing changeswhen initiating treatment with brexpiprazole to achieve the sameclinical response: effective treatment of schizophrenia and majordepressive disorder. Prior to this invention, the standard of care leftsuch obese patients untreated or undertreated, delaying resolution oftheir condition.

The invention addresses additional complexities and identifies modifieddosing regimens that are critical to safely and effectively initiatetreatment with brexpiprazole. In various embodiments the presentinvention is directed, inter alia, to specific dose adjustments thatavoid under-treatment but do not exceed known exposure levels whichwould expose patients to serious side effects. In various embodimentsthe present invention is directed, inter alia, to specific dosingregimens needed for different indications and for different CYP2D6metabolizer status.

Expected Drug Profile

The expected blood plasma brexpiprazole concentrations during theinitiation of brexpiprazole treatment (days 1-28) for patients withschizophrenia and major depressive disorder (MDD) according to thebrexpiprazole FDA label (revised in March 2020) are shown in FIG. 1A andFIG. 1B, respectively. Because there was no recognition in the art thatthe dosing regimen for initiating treatment with brexpiprazole should beadjusted based on the obesity status of the patient, obesity status wasnot expected to affect the blood plasma concentration of brexpiprazole.In other words, obese patients with schizophrenia or major depressivedisorder were expected to have qualitatively similar blood plasmaconcentrations as normal weight patients.

The present inventors are not aware of anything in the art which wouldcontradict the use of the same brexpiprazole dosing regimen for obeseand normal-weight patients disclosed in the FDA-approved label forbrexpiprazole. It is acknowledged in the art that body size and obesitycan have an effect on the pharmacokinetics of some drugs; however, theclinical relevance of this effect is highly dependent on the particularcharacteristics of that drug. For example, Hanley et al., in reviewingthe effects of obesity on drug pharmacokinetics, found that appropriatedrug dosing should be individualized to the particular drug at issue,and that the distribution of a drug in obese patients cannot be entirelypredicted based on the physiochemical attributes of the drug (e.g.,lipophilicity, hydrophilicity) alone. (Hanley et al., Effect of Obesityon the Pharmacokinetics of Drugs in Humans, Clin. Pharmacokinet 2010,49(2): 70-87.) The pharmacokinetic studies leading to the approval ofbrexpiprazole did not include patients with BMI >35 kg/m², and previousstudies have found that the effect of weight on the pharmacokinetics ofbrexpiprazole was less than 20% and was not a significant determinant inbrexpiprazole pharmacokinetics. The inventors are not aware of anyevidence in the prior art that suggests that there is any clinicallyimportant effect of obesity on brexpiprazole pharmacokinetics that wouldrequire any difference in the brexpiprazole dosing regimen between obeseand normal-weight patients. Thus, at the time of the presentapplication, the FDA-approved dosing instructions for obese and normalweight patients are the same. However, the present invention is based onthe discovery that a patient's body size significantly affects the timeit takes a patient to reach therapeutic levels of brexpiprazole. SeeFIG. 2A and FIG. 2B.

Without this new information, it was not appreciated in the art that,using the instructions for brexpiprazole dosing found in the existingFDA-approved labels for brexpiprazole (at the time of the presentdisclosure), obese patients do not reach therapeutic levels ofbrexpiprazole as quickly as normal weight patients upon initiatingbrexpiprazole treatment; or alternatively stated, it has been discoveredthat it takes significantly longer to reach therapeutic levels ofbrexpiprazole in obese patients compared to normal-weight patients usingthe FDA-approved label's instructions.

The REXULTI® label teaches reducing the dose of brexpiprazole to half ofthe usual dosage if the patient is a CYP2D6 poor metabolizer (CYP2D6 PMsor simply “PMs”). Similarly, the present inventors have also found thatthe time required to reach therapeutic levels of brexpiprazole for obesepatients who are also PMs, using the FDA-approved brexpiprazole dosingregimen (i.e., half of the recommended dose), is longer than fornormal-weight PMs.

Thus, prior to the present invention, for obese patient populations (asdescribed herein), the patient's psychiatric disorders (e.g.,schizophrenia and major depressive disorder) were unknowingly leftundertreated because these patients did not reach therapeuticconcentrations in a similar time as normal-weight patient. Suchunintended undertreatment of psychiatric disorders is potentially quiteserious, as complications of untreated psychiatric disorders includesuicide attempts, anxiety, depression, alcohol or drug abuse, inabilityto work or attend school, financial problems, homelessness, socialisolation, health and medical problems, being victimized, and aggressivebehavior.

Thus, the development of the presently disclosed new dosage regimensallow obese patients to reach therapeutic levels of brexpiprazole asquickly as normal-weight patients without putting them at risk ofakathisia.

The present disclosure provides an alternative dosing regimen fortreating a patient with a psychiatric disorder, such as schizophrenia ormajor depressive disorder, with brexpiprazole, wherein the patient hasone or more of the following characteristics: (i) a BMI of at leastabout 35; (ii) % IBW of at least about 150%; (iii) waist size greaterthan about 42 inches; (iv) % body fat greater than about 40%; (v) %android body fat greater than about 40%; (vi) % gynoid body fat greaterthan about 40%; (vii) total body fat greater than about 40 kg; or (viii)CYP2D6 poor metabolizer.

The present inventors have discovered that patients dosed according tothe brexpiprazole FDA label dosage instructions that have any of theaforementioned characteristics do not reach therapeutic levels ofbrexpiprazole as quickly as non-obese CYP2D6 EM patients. In particular,patients that are obese (e.g., have one or more of the followingcharacteristics: (i) a BMI of at least about 35 kg/m²; (ii) % IBW of atleast about 150%; (iii) waist size greater than about 42 inches; (iv) %body fat greater than about 40%; (v) % android body fat greater thanabout 40%; (vi) % gynoid body fat greater than about 40%; (vii) totalbody fat greater than about 40 kg) or obese (as defined herein) CYP2D6poor metabolizers (PM) take longer to reach the similar therapeuticconcentrations of patients that are normal-weight CYP2D6 extensivemetabolizers (EM) (FIG. 2A and FIG. 2B). The brexpiprazole dosageregimen recommended by the FDA label is shown in Table 1.

TABLE 1 Brexpiprazole Dosing According to FDA Label Indication StartingDose Recommended Dose Maximum Dose Major depressive 0.5-1 mg/day 2mg/day 3 mg/day disorder (MDD) Schizophrenia 1 mg/day 2-4 mg/day 4mg/day

For adjunctive treatment for MDD, the FDA label recommends a startingdose of brexpiprazole of 0.5 mg, then titrating the starting dose ofbrexpiprazole up to 1 mg (if starting at 0.5 mg) once daily, and then upto the recommended dosage of 2 mg once daily. Alternatively, the FDAlabel recommends using a starting dose of 1 mg once daily, thentitrating up to the recommended dosage of 2 mg once daily. Dosageincreases should occur at weekly intervals based on the patient'sclinical response and tolerability. The maximum daily dosage is 3 mg.

For treatment of schizophrenia, the label teaches starting with aninitial or starting dose of 1 mg of brexpiprazole administered oncedaily on each of the first 4 days of treatment (days 1-4), thenadministering 2 mg once daily on the next 3 days of treatment (day 5through day 7), and then administering 4 mg once daily on day 8 based onthe patient's clinical response and tolerability. The maximum dailydosage is 4 mg.

The dosage for CYP2D6 poor metabolizers (patients classified as having aCYP2D6 enzyme phenotype with little or no CYP2D6 activity compared tonormal levels of CYP2D6 activity) is half of the dose that wouldotherwise be administered if the patent was not a CYP2D6 poormetabolizer.

Applicants have developed a modified brexpiprazole dosage regimen forinitiating treatment with brexpiprazole that allows obese patientsand/or obese CYP2D6 PM (poor metabolizer) patients to reachtherapeutically effective concentrations at a similar time compared tonormal-weight CYP2D6 EM patients (extensive metabolizers; i.e., patientsclassified as having a CYP2D6 enzyme phenotype with normal levels ofCYP2D6 activity) (FIGS. 3-9). As Table D of Example 2 reveals, oneembodiment of the modified dosage regimen of the present inventionprovides double the total daily dose of brexpiprazole of the FDA labelon days 1-7. As Table J in Example 3 reveals, other embodiments of themodified dosage regimen provide double the total daily dose ofbrexpiprazole of the FDA label on days 1-14 or days 1-21.

The FDA label for brexpiprazole (REXULTI® revised March 2020) neitherrecognizes that obese CYP2D6 EM patients and/or obese CYP2D6 PM patientsdo not reach therapeutic levels as quickly as normal-weight CYP2D6 EMpatients, nor does it provide a dosage regimen that corrects this(hitherto unknown) problem. Instead, the label implicitly teaches thatobese CYP2D6 EM should receive the same dose as normal-weight CYP2D6 EM,and explicitly teaches that all CYP2D6 PM patients (i.e., normal-weightand obese) should receive half of the dose that CYP2D6 EM patientsreceive. However, Applicants have discovered that administering the samedose to obese CYP2D6 EM that normal-weight CYP2D6 EM receive, and halfof the dose to obese CYP2D6 PM (as taught by the FDA label) causes obeseCYP2D6 EM and obese CYP2D6 PM patients to reach therapeuticbrexpiprazole concentrations more slowly than normal-weight CYP2D6 EMpatients. Administering brexpiprazole according to a modified dosageregimen provided herein enables obese and/or obese CYP2D6 PM patients toapproach therapeutic levels of brexpiprazole as quickly as normal-weightCYP2D6 EM patients (FIGS. 3-9).

In embodiments, the disclosure provides method of initiating treatmentof schizophrenia with brexpiprazole in an obese patient who is not aCYP2D6 poor metabolizer, comprising: (a) administering 1 mgbrexpiprazole twice daily on each of the first 4 days of brexpiprazoletreatment; (b) administering 2 mg brexpiprazole twice daily on each ofthe next 3 days following step (a); and then (c) administering arecommended dose of brexpiprazole once daily thereafter; wherein theobese patient has one or more of the following characteristics: (i) BMIof at least about 35; (ii) % IBW of at least about 150%; (iii) waistsize greater than about 42 inches; (iv) % body fat greater than about40%; (v) % android body fat greater than about 40%; (vi) % gynoid bodyfat greater than about 40%; or (vii) total body fat greater than about40 kg. In embodiments, the recommended dose of brexpiprazole is 2-4mg/day. In embodiments, the recommended dose of brexpiprazole is 2mg/day. In embodiments, the recommended dose of brexpiprazole is 2.25mg/day. In embodiments, the recommended dose of brexpiprazole is 2.5mg/day. In embodiments, the recommended dose of brexpiprazole is 2.75mg/day. In embodiments, the recommended dose of brexpiprazole is 3mg/day. In embodiments, the recommended dose of brexpiprazole is 3.25mg/day. In some embodiments, the recommended dose of brexpiprazole is3.5 mg/day. In embodiments, the recommended dose of brexpiprazole is3.75 mg/day. In embodiments, the recommended dose of brexpiprazole is 4mg/day.

In embodiments, the disclosure provides a method of initiating treatmentof schizophrenia with brexpiprazole in an obese patient who is a CYP2D6poor metabolizer, comprising: (a) administering 0.5 mg brexpiprazoletwice daily on each of the first 4 days of brexpiprazole treatment; (b)administering 1 mg brexpiprazole twice daily on each of the next 3 daysfollowing step (a); and then (c) administering half of a recommendeddaily dose of brexpiprazole once daily thereafter; wherein the obesepatient has one or more of the following characteristics: (i) BMI of atleast about 35; (ii) % IBW of at least about 150%; (iii) waist sizegreater than about 42 inches; (iv) % body fat greater than about 40%;(v) % android body fat greater than about 40%; (vi) % gynoid body fatgreater than about 40%; or (vii) total body fat greater than about 40kg. In embodiments, half of the recommended dose of brexpiprazole is 1-2mg/day. In embodiments, half of the recommended dose of brexpiprazole is1 mg/day. In embodiments, half of the recommended dose of brexpiprazoleis 1.25 mg/day. In embodiments, half of the recommended dose ofbrexpiprazole is 1.5 mg/day. In embodiments, half of the recommendeddose of brexpiprazole is 1.75 mg/day. In embodiments, half of therecommended dose of brexpiprazole is 2 mg/day.

In embodiments, the disclosure provides a method of initiatingadjunctive treatment of major depressive disorder with brexpiprazole inan obese patient who is not a CYP2D6 poor metabolizer, comprising: (a)administering either 0.5 or 1 mg brexpiprazole twice daily on each ofthe first 7 days of brexpiprazole treatment; (b) administering doublethe individual brexpiprazole dose of step (a) once daily on each of thenext 7 days following step (a); and then (c) administering therecommended daily dose of brexpiprazole once daily thereafter; whereinthe obese patient has one or more of the following characteristics: (i)BMI of at least about 35; (ii) % IBW of at least about 150%; (iii) waistsize greater than about 42 inches; (iv) % body fat greater than about40%; (v) % android body fat greater than about 40%; (vi) % gynoid bodyfat greater than about 40%; or (vii) total body fat greater than about40 kg. In embodiments of the method of initiating adjunctive treatmentof major depressive disorder with brexpiprazole, step (a) isadministering 0.5 mg brexpiprazole twice daily for each of the first 7days of brexpiprazole treatment, and step (b) is administering 1 mgbrexpiprazole once daily for each of the next 7 days following step (a).In embodiments of the method of initiating treatment of major depressivedisorder with brexpiprazole, step (a) is administering 1 mgbrexpiprazole twice daily for each of the first 7 days of brexpiprazoletreatment, and step (b) is administering 2 mg brexpiprazole once dailyfor each of the next 7 days following step (a). In embodiments, therecommended daily dose of step (c) is 2-3 mg/day. In embodiments, therecommended daily dose of step (c) is 2 mg/day. In embodiments, therecommended daily dose of step (c) is 2.25 mg/day. In embodiments, therecommended daily dose of step (c) is 2.5 mg/day. In embodiments, therecommended daily dose of step (c) is 2.75 mg/day. In embodiments, therecommended daily dose of step (c) is 3 mg/day.

In embodiments, the disclosure provides a method of initiatingadjunctive treatment of major depressive disorder with brexpiprazole inan obese patient who is a CYP2D6 poor metabolizer, comprising: (a)administering 0.5 mg brexpiprazole twice daily on each of the first 7days of brexpiprazole treatment; (b) administering 1 mg twice daily oneach of the next 7 days following step (a); and then (c) administeringhalf of the recommended daily dose of brexpiprazole once dailythereafter; wherein the obese patient has one or more of the followingcharacteristics: (i) BMI of at least about 35; (ii) % IBW of at leastabout 150%; (iii) waist size greater than about 42 inches; (iv) % bodyfat greater than about 40%; (v) % android body fat greater than about40%; (vi) % gynoid body fat greater than about 40%; or (vii) total bodyfat greater than about 40 kg. In embodiments, half of the recommendeddaily dose of step (c) is 1-1.5 mg/day. In embodiments, half of therecommended daily dose of step (c) is 1 mg/day. In embodiments, half ofthe recommended daily dose of step (c) is 1.25 mg/day. In embodiments,half of the recommended daily dose of step (c) is 1.5 mg/day. Inembodiments, half of the recommended daily dose of step (c) is 1.75mg/day. In embodiments, half of the recommended daily dose of step (c)is 2 mg/day.

In embodiments, the disclosure provides method of initiating adjunctivetreatment of major depressive disorder with brexpiprazole in an obesepatient who is a CYP2D6 poor metabolizer, comprising: (a) administering0.25 mg brexpiprazole twice daily on each of the first 7 days ofbrexpiprazole treatment; (b) administering 0.5 twice daily on each ofnext 7 days following step (a); (c) administering 1 mg daily twice oneach of the next 7 days following step (b); and then (d) administeringhalf of the recommended daily dose of brexpiprazole once dailythereafter; wherein the obese patient has one or more of the followingcharacteristics: (i) BMI of at least about 35; (ii) % IBW of at leastabout 150%; (iii) waist size greater than about 42 inches; (iv) % bodyfat greater than about 40%; (v) % android body fat greater than about40%; (vi) % gynoid body fat greater than about 40%; or (vii) total bodyfat greater than about 40 kg. In some embodiments, half of therecommended daily dose of step (c) is 1-1.5 mg/day. In some embodiments,half of the recommended daily dose of step (c) is 1 mg/day. In someembodiments, half of the recommended daily dose of step (c) is 1.25mg/day. In some embodiments, half of the recommended daily dose of step(c) is 1.5 mg/day. In some embodiments, half of the recommended dailydose of step (c) is 1.75 mg/day. In some embodiments, half of therecommended daily dose of step (c) is 2 mg/day.

Applicant also surprisingly discovered that normal-weight CYP2D6 PMpatients do not reach therapeutic levels as quickly as normal-weightCYP2D6 EM (FIG. 1A and FIG. 1B). Administering brexpiprazole accordingto a modified dosage regimen provided herein enables normal-weightCYP2D6 PM patients to approach therapeutic levels of brexpiprazole asquickly as normal-weight CYP2D6 EM patients (FIGS. 5, 11, and 12)

In embodiments, the disclosure provides a method of initiating treatmentof schizophrenia with brexpiprazole in a normal-weight patient who is aCYP2D6 poor metabolizer, comprising: (a) administering 0.5 mgbrexpiprazole twice daily on each of the first 4 days of brexpiprazoletreatment; (b) administering 1 mg brexpiprazole twice daily on each ofthe next 3 days following step (a); and then (c) administering half ofthe recommended dose of brexpiprazole once daily thereafter, wherein thenormal-weight patient has at least one of the following characteristics:(i) BMI less than about 35 kg/m²; (ii) % IBW less than about 150%; (iii)waist size less than about 42 inches; (iv) % body fat less than about40%; (v) % android body fat less than about 40%; (vi) % gynoid body fatless than about 40%; or (vii) total body fat less than about 40 kg. Inembodiments, half of the recommended dose of brexpiprazole is 1-2mg/day. In embodiments, half of the recommended dose of brexpiprazole is1 mg/day. In embodiments, half of the recommended dose of brexpiprazoleis 1.25 mg/day. In embodiments, half of the recommended dose ofbrexpiprazole is 1.5 mg/day.

In embodiments, the disclosure provides a method of initiatingadjunctive treatment of major depressive disorder with brexpiprazole ina normal-weight patient who is not a CYP2D6 poor metabolizer,comprising: (a) administering either 0.25 or 0.5 mg brexpiprazole twicedaily on each of the first 7 days of brexpiprazole treatment; (b)administering double the individual brexpiprazole dose of step (a) oncedaily on each of the next 7 days following step (a); and then (c)administering the recommended daily dose of brexpiprazole once dailythereafter; wherein the normal-weight patient has at least one of thefollowing characteristics: (i) BMI less than about 35 kg/m²; (ii) % IBWless than about 150%; (iii) waist size less than about 42 inches; (iv) %body fat less than about 40%; (v) % android body fat less than about40%; (vi) % gynoid body fat less than about 40%; or (vii) total body fatless than about 40 kg. In embodiments of the method of initiatingadjunctive treatment of major depressive disorder with brexpiprazole,step (a) is administering 0.25 mg brexpiprazole twice daily for each ofthe first 7 days of brexpiprazole treatment, and step (b) isadministering 0.5 mg brexpiprazole once daily for each of the next 7days following step (a). In embodiments of the method of initiatingtreatment of major depressive disorder with brexpiprazole, step (a) isadministering 0.5 mg brexpiprazole twice daily for each of the first 7days of brexpiprazole treatment, and step (b) is administering 1 mgbrexpiprazole once daily for each of the next 7 days following step (a).In embodiments, half of the recommended dose of brexpiprazole is 1-1.5mg/day. In embodiments, half of the recommended dose of brexpiprazole is1 mg/day. In embodiments, half of the recommended dose of brexpiprazoleis 1.25 mg/day. In embodiments, half of the recommended dose ofbrexpiprazole is 1.5 mg/day.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1A shows the plasma levels of brexpiprazole in normal-weight CYP2D6EM and CYP2D6 PM patients with schizophrenia that are treated accordingto the brexpiprazole FDA label. While steady-state brexpiprazole plasmalevels of CYP2D6 PM patients are lower than brexpiprazole plasma levelsof CYP2D6 EM patients, these steady-state levels are consideredtherapeutically effective concentrations for CYP2D6 PM patients.

FIG. 1B shows the plasma levels of brexpiprazole in normal-weight CYP2D6EM and CYP2D6 PM patients with major depressive disorder (MDD) that aretreated according to the brexpiprazole FDA label, with a starting doseof 0.5 mg. While steady-state brexpiprazole plasma levels in CYP2D6 PMpatients are lower than brexpiprazole plasma levels in CYP2D6 EMpatients, these steady-state levels are considered therapeuticallyeffective concentrations for CYP2D6 PM patients.

FIG. 2A shows the plasma levels of brexpiprazole in normal-weight CYP2D6EM, normal-weight CYP2D6 PM, obese CYP2D6 EM, and obese CYP2D6 PMpatients with schizophrenia that are treated according to thebrexpiprazole FDA label. Obese CYP2D6 EM and obese CYP2D6 PM patientstake longer to reach therapeutic concentrations of brexpiprazole thannormal-weight CYP2D6 EM patients, and may not reach therapeuticconcentrations at all in the first 28 days of brexpiprazoleadministration.

FIG. 2B shows the plasma levels of brexpiprazole in normal-weight CYP2D6EM, normal-weight CYP2D6 PM, obese CYP2D6 EM, and obese CYP2D6 PMpatients with MDD that are treated according to the brexpiprazole FDAlabel, with a starting dose of 0.5 mg. Obese CYP2D6 EM and obese CYP2D6PM patients take longer to reach therapeutic concentrations ofbrexpiprazole than normal-weight CYP2D6 EM patients, and may not reachtherapeutic concentrations at all in the first 28 days of brexpiprazoleadministration.

FIG. 3 shows the plasma levels of brexpiprazole over time of obeseCYP2D6 EM schizophrenia patients that are administered 1 mgbrexpiprazole twice daily for days 1-4 and 2 mg BID for days 5-7 (Table3. Modified Dosing Regimen 1). Obese CYP2D6 EM patients treatedaccording to the disclosed modified dosage regimen reach therapeuticconcentrations that are similar to normal-weight CYP2D6 EM patientstreated according to the brexpiprazole FDA label.

FIG. 4 shows the plasma levels of brexpiprazole over time of obeseCYP2D6 PM schizophrenia patients that are administered 0.5 mgbrexpiprazole twice daily on days 1-4, 1 mg BID on days 5-7, and thenare administered 2 mg brexpiprazole twice daily for days 8-14 (Table 3.Modified Dosing Regimen 2). Obese CYP2D6 PM patients treated accordingto the modified dosage regimen reach therapeutic concentrations ofbrexpiprazole in a similar time as normal-weight CYP2D6 EM patientstreated according to the brexpiprazole FDA label. When administeredbrexpiprazole according to the FDA label, obese CYP2D6 PM patients donot reach therapeutic concentrations in the first 28 days ofadministration.

FIG. 5 shows the plasma brexpiprazole concentration over time ofnormal-weight CYP2D6 PM schizophrenia patients that are administeredbrexpiprazole according to the modified dosage regimen of Table D.

FIG. 6 shows the plasma levels of brexpiprazole over time of obeseCYP2D6 EM major depressive disorder patients that are administered 0.5mg brexpiprazole twice daily for the first seven days (Table 4. ModifiedDosing Regimen A). Obese CYP2D6 EM patients treated according to thedisclosed modified dosage regimen reach therapeutic concentrations thatare similar to normal-weight CYP2D6 EM patients treated according to thebrexpiprazole FDA label.

FIG. 7 shows the plasma levels of brexpiprazole over time of obeseCYP2D6 EM major depressive disorder patients that are administered 1 mgbrexpiprazole twice daily for the first seven days (Table 4. ModifiedDosing Regimen B). Obese CYP2D6 EM patients treated according to themodified dosage regimen reach therapeutic concentrations ofbrexpiprazole in a similar time as normal-weight CYP2D6 EM patientstreated according to the brexpiprazole FDA label.

FIG. 8 shows the plasma levels of brexpiprazole over time of obeseCYP2D6 PM major depressive disorder patients that are administered 0.25mg brexpiprazole twice daily for the first seven days, 0.5 mg twicedaily for days 8-15, and 1 mg twice daily for days 16-21 (Table 4.Modified Dosing Regimen C). Obese CYP2D6 PM patients treated accordingto the disclosed modified dosage regimen reach therapeuticconcentrations that are similar to normal-weight CYP2D6 EM patientstreated according to the brexpiprazole FDA label. When administeredbrexpiprazole according to the FDA label, obese CYP2D6 PM patients donot reach therapeutic concentrations in the first 28 days ofadministration.

FIG. 9 shows the plasma levels of brexpiprazole over time of obeseCYP2D6 PM major depressive disorder patients that are administered 0.5mg brexpiprazole twice daily for the first 7 days, and 1 mg twice dailyon days 8-14 (Table 4. Modified Dosing Regimen D). Obese CYP2D6 PMpatients treated according to the modified dosage regimen reachtherapeutic concentrations of brexpiprazole in a similar time asnormal-weight CYP2D6 EM patients treated according to the brexpiprazoleFDA label. When administered brexpiprazole according to the FDA label,obese CYP2D6 PM patients do not reach therapeutic concentrations in thefirst 28 days of administration.

FIG. 10 shows the plasma levels of brexpiprazole over time for an obeseCYP2D6 EM when the patient is administered brexpiprazole (i) accordingto the brexpiprazole FDA label; (ii) BID for 7 days according to amodified dosing regimen of the disclosure; and (iii) BID for 14 days.When BID dosing exceeds the modified dosing of the disclosure, plasmalevels elevate significantly above those of normal-weight CYP2D6 EM andpresent a risk of serious side effects.

FIG. 11 shows the plasma levels of brexpiprazole over time ofnormal-weight CYP2D6 PM major depressive disorder patients that areadministered 0.25 mg brexpiprazole twice daily for the first 7 days(Table 4. Modified Dosing Regimen E). Normal-weight CYP2D6 PM patientstreated according to the modified dosage regimen reach therapeuticconcentrations of brexpiprazole in a similar time as normal-weightCYP2D6 EM patients treated according to the brexpiprazole FDA label.

FIG. 12 shows the plasma levels of brexpiprazole over time ofnormal-weight CYP2D6 PM major depressive disorder patients that areadministered 0. 5 mg brexpiprazole twice daily for the first 7 days(Table 4. Modified Dosing Regimen F). Normal-weight CYP2D6 PM patientstreated according to the modified dosage regimen reach therapeuticconcentrations of brexpiprazole in a similar time as normal-weightCYP2D6 EM patients treated according to the brexpiprazole FDA label.

DETAILED DESCRIPTION Definitions

Any reference to brexpiprazole herein also encompasses all of thepharmaceutically acceptable isomers (e.g., stereoisomers), solvates,hydrates, polymorphs, salts, and prodrugs (e.g., esters and phosphates).

As used herein, “normal,” “normal-weight,” or other derivations orvariations thereof refers to a non-obese state in a person who can haveat least one of the following characteristics: BMI less than about 35kg/m², % IBW less than about 150%, waist size less than about 42, % bodyfat less than about 40%, % android body fat less than about 40%, %gynoid body fat less than about 40%, and total body fat less than about40 kg. Unless otherwise modified, “normal metabolizer” also means anextensive CYP2D6 metabolizer.

As used herein, the terms “reference dose”, “reference daily dose”,“recommended dose”, or “usual dose” refer to the maintenance dosage ofbrexpiprazole, as indicated on the manufacture's FDA-approved label(e.g., the most recent FDA-approved label in effect as of March, 2020).The REXULTI® label also refers to a “Starting Dose” and a “Maximum Dose”as distinct from the “Recommended Dose”. While colloquially the term“recommended” or “usual” dose could refer to any dose taught in theREXULTI® label, in this disclosure the term “recommended dose” refersmore narrowly to doses recommended for maintenance treatment (includingthe “maximum dose” suitable for such treatment) of a normal weight,extensive CYP2D6 metabolizer patients. Thus, where the REXULTI® labelteaches administering 2 mg once daily up to a maximum dose of 3 mg oncedaily for an MDD patient, such dose or dose range is a “recommended”dose or dose range. Where the REXULTI® label teaches reducing the “usualdosage by half” for “Known CYP2D6 Metabolizers”, the recommended orusual dose as used herein is the dose “recommended” or “usual” forpatients who are not CYP2D6 PMs.

It is common for a particular drug to be approved for multiple differentindications, and each indication may have a different reference orrecommended dose. For example, the “recommended dose” listed in theMarch 2020 REXULTI® label indicates that 2 to 3 mg once daily is the“recommended dose” for MDD and 2 to 4 mg once daily is the “recommendeddose” for schizophrenia.

As used herein “therapeutic concentration” refers to the steady statepharmacokinetic profile of brexpiprazole based on the pharmacokineticstudies supporting FDA approval of brexpiprazole as measured innormal-weight patients. As shown in FIG. 1A and FIG. 1B, normal-weightpatients treated with brexpiprazole achieve steady statepharmacokinetics after the initiation phase of treatment, typicallyaround days 14-21 of treatment according to FIG. 1A and FIG. 1B. Becausethe blood plasma levels in FIG. 1A and FIG. 1B represent averages fromall patients, some deviation from the average steady statepharmacokinetic profile in a particular patient or patient population isexpected and is acceptable in the art. The modified dosing regimens ofthe present disclosure bring the blood plasma concentrations ofbrexpiprazole in obese patients and obese CYP2D6 PM patients withinappropriate degrees of variation of the average steady statepharmacokinetic profile of normal-weight CYP2D6 EM patients shown inFIG. 1A and FIG. 1B. This enables obese patients or obese CYP2D6 PMpatients to reach therapeutic concentrations of brexpiprazole at asimilar time as normal-weight CYP2D6 EM patients, allowing for betterclinical response. It is not necessary for the pharmacokinetic profileof the modified dosing regimens disclosed herein to overlap exactly withthe pharmacokinetic profile of brexpiprazole based on thepharmacokinetic studies supporting FDA approval.

As used herein “BID” refers to twice daily administration.

As used herein “QD” refers to once daily administration.

Brexpiprazole

Brexpiprazole is an atypical antipsychotic, available as REXULTI®, to beused as an adjunctive therapy to antidepressants for the treatment ofmajor depressive disorder and as a treatment for schizophrenia. The FDAlabel of REXULTI® (Otsuka and Lundbeck, revised March 2020) isincorporated by reference herein in its entirety. Brexpiprazole is7-{4-[4-(1-Benzothiophen-4-yl)piperazin-1-yl]butoxy}quinolin-2(1H)-one.The empirical formula is C₂₅H₂₇N₃O₂S and its molecular weight is 433.57.

The chemical structure of brexpiprazole is

The FDA label provides the following dosage instructions for adjunctivetreatment for major depressive disorder: The starting dosage forbrexpiprazole (REXULTI®) as adjunctive treatment is 0.5 mg or 1 mg oncedaily, taken orally with or without food. Titrate to 1 mg once daily,then up to the recommended dosage of 2 mg once daily. Dosage increasesshould occur at weekly intervals based on the patient's clinicalresponse and tolerability. The maximum recommended daily dosage is 3 mg.Periodically reassess to determine the continued need and appropriatedosage for treatment.

The FDA label provides the following dosage instructions forschizophrenia: The starting dosage for brexpiprazole (REXULTI®) is 1 mgonce daily on Days 1 to 4, taken orally with or without food. Therecommended brexpiprazole (REXULTI®) dosage is 2 mg to 4 mg once daily.Titrate to 2 mg once daily on Day 5 through Day 7, then to 4 mg on Day 8based on the patient's clinical response and tolerability. The maximumdaily dosage is 4 mg.

The FDA label provides dosage modifications for CYP2D6 Poor Metabolizersand for concomitant use with CYP Inhibitors or Inducers: Dosageadjustments are recommended in patients who are known cytochrome P450(CYP) 2D6 poor metabolizers and in patients taking concomitant CYP3A4inhibitors or CYP2D6 inhibitors or strong CYP3A4 inducers (see Table 2).If the coadministered drug is discontinued, adjust the REXULTI dosage toits original level. If the coadministered CYP3A4 inducer isdiscontinued, reduce the REXULTI dosage to the original level over 1 to2 weeks.

TABLE 2 Adjusted Brexpiprazole Factors (REXULTI ®) Dosage CYP2D6 PoorMetabolizers CYP2D6 poor metabolizers Administer half of the usual dose.Known CYP2D6 poor metabolizers taking Administer a quarter of thestrong/moderate CYP3A4 inhibitors usual dose. Patients taking CYP2D6Inhibitors and/or CYP3A4 Inhibitors Strong CYP2D6 inhibitors(paroxetine, Administer half of the usual fluoxetine) dose. StrongCYP3A4 inhibitors Administer half of the usual dose. Strong/moderateCYP2D6 inhibitors with Administer a quarter of the strong/moderateCYP3A4 inhibitors usual dose. Patients taking CYP3A4 Inducers StrongCYP3A4 Inducers Double usual dose over 1 to 2 weeks

Applicant found that the brexpiprazole (REXULTI®) dosage instructionsfor initiating treatment with brexpiprazole do not providetherapeutically effective levels of brexpiprazole for patients that areobese or obese CYP2D6 PM as quickly as for normal-weight CYP2D6 EMs.

Dosage Regimens

The various dosing methods of the present invention, as describedherein, comprise initiating treatment by administering an elevated dailydose of brexpiprazole for one or more defined time periods, then at anappropriate time (as described herein), administering theFDA-recommended dose appropriate for the indication (e.g., schizophreniaor major depressive disorder). The initial, elevated daily dose isadministered in the form of multiple daily doses, as a single elevateddose would result in sharp “peaks” in the plasma level that could causeserious side effects such as akathisia. The multiple daily brexpiprazoledoses administered at the initiation of brexpiprazole treatmentaccording to various embodiments of the present invention are typicallyadministered in the form of two equal daily doses, that when combinedprovided a daily dose of brexpiprazole that is higher than the startingdose of brexpiprazole described in the REXULTI® label. Typically, themultiple daily brexpiprazole doses administered at the initiation ofbrexpiprazole treatment provide a daily dose that is double the startingdose of brexpiprazole described in the REXULTI® label. However, in viewof the discovery described herein, the initial dose of brexpiprazoleaccording to the present invention could comprise unequal doses, and/orcould be administered in more than two (e.g., three or four) dailydoses. Alternatively, instead of administering multiple daily doses atthe initiation of brexpiprazole treatment, the starting doses describedherein (e.g. double the starting dose of brexpiprazole described in theREXULTI® label) may be administered once daily in a sustained orextended release formulation. Such a formulation can releasebrexpiprazole over the course of a day in a manner that is similar totwice (or more) daily administration of brexpiprazole. The guidingprinciple for initiating administration of brexpiprazole according tothe methods disclosed herein is to increase the daily dose ofbrexpiprazole for a defined period such that obese CYP2D6 EM or obeseCYP2D6 PM patients reach therapeutic plasma levels of brexpiprazole morequickly than would be obtained for such patients using the dosingregimens provided in FDA-approved brexpiprazole labels prior to thepresent invention. Further, the use of multiple daily doses (e.g., BIDdosing) to provide such elevated daily doses of brexpiprazole (e.g.,elevated relative to the daily “Starting Dose” and/or “Recommended Dose”provided in REXULTI® labels published prior to the present invention)are designed to ensure that no single dose elevates the brexpiprazoleplasma levels of such patients to levels which would increase the riskof serious side effects such as akathisia. The limited duration of suchmultiple dosing prior to reverting to the recommended or usualmaintenance dose of brexpiprazole is also designed to prevent elevatedplasma levels of brexpiprazole that could increase the risk of seriousside effects such as akathisia. FIG. 10 shows the effect of BID dosingin an obese schizophrenia patient during the first 14 days of treatment.After 7 days of BID dosing, the plasma levels of brexpiprazole begin toelevate above the blood plasma levels that would occur in normal-weightpatients treated according to the FDA label, and the increased exposurebecomes more pronounced and potentially more dangerous each day of BIDtreatment through day 14. This results in blood plasma concentrationsthat present an unacceptable risk of serious side effects.

The skilled artisan understands that in various embodiments, themagnitude and/or number of initial doses of brexpiprazole can be varied,along with the duration of the initial dosing period, such that theobese patients (EM and PM) according to the present invention reachtherapeutic plasma levels of brexpiprazole more rapidly than they wouldif using the dosing regimens provided in FDA-approved brexpiprazolelabels prior to the present invention, without increasing the risk ofserious side effects.

The skilled artisan understands that the REXULTI® label (March 2020)contains provisions for dose adjustments in the case of concomitant usewith a strong CYP2D6 or strong CYP3A4 inhibitor (e.g., administer halfof the dose), or concomitant use with a strong CYP2D6 and strong CYP3A4inhibitor (e.g., administer a quarter of the dose). These doseadjustments are applied to any relevant recommended dose or patientpopulation.

In some embodiments, the modified dosage regimens described hereinprovide therapeutically effective levels of brexpiprazole for certainpatient populations (e.g., for patients that are obese or are obeseCYP2D6 poor metabolizers).

In some embodiments, the modified dosage regimens of the presentinvention provide a starting dose. As used herein, a “starting dose” isthe lowest dose of brexpiprazole that is administered when initiatingtreatment with brexpiprazole. In some embodiments, the starting dose isadministered on day 1 of brexpiprazole treatment. In some embodiments,the starting dose is administered on days 1-4 of brexpiprazoletreatment. In some embodiments, the starting dose is administered ondays 1-7 of brexpiprazole treatment. In some embodiments, the startingdose of the modified brexpiprazole dosage regimens of the presentinvention is double that of the starting dose instructed by thebrexpiprazole (REXULTI®) FDA label (March 2020). In some embodiments,the starting dose of the modified brexpiprazole dosage regimen is triplethat instructed by the brexpiprazole (REXULTI®) FDA label (March 2020).In some embodiments, the starting dose on days 1-4 of the modifiedbrexpiprazole dosage regimen is double that of the starting doseinstructed by the brexpiprazole (REXULTI®) FDA label (March 2020) fordays 1-4. In some embodiments, the starting dose on days 1-7 of themodified brexpiprazole dosage regimen is double that of the startingdose instructed by the brexpiprazole (REXULTI®) FDA label (March 2020)for days 1-7. In some embodiments, the dose administered on days 8-14 ordays 8-21 of the modified brexpiprazole dosage regimen is double that ofthe dose instructed by the brexpiprazole (REXULTI®) FDA label (March2020) for days 8-14 or days 8-21. As used herein, phrases such as “days1-4”, “days 5-7”, “days 1-7” and the like refer to days after firstinitiating the administration of brexpiprazole. That is, “day 1” is thefirst day brexpiprazole is administered to the patient upon initiatingtreatment, day 7 is the seventh day of brexpiprazole treatment, etc.Initiating brexpiprazole treatment can refer to the first administrationto a brexpiprazole-naive patient who has never been administeredbrexpiprazole, or to a patient who may have been administeredbrexpiprazole in the past, but has ceased treatment with brexpiprazolefor a period sufficient to require re-introduction of brexpiprazole witha lower starting dose of brexpiprazole before increasing to therecommended dose.

In some embodiments, a patient is administered a starting dose of about0.25 mg to about 3 mg of brexpiprazole, for example, about 0.25, about0.5 mg, about 0.75 mg, about 1 mg, about 1.25 mg, about 1.5 mg, about1.75 mg, about 2 mg, about 2.25 mg, about 2.5 mg, about 2.75 mg, orabout 3 mg of brexpiprazole. In some embodiments, a patient isadministered a total daily dose of 0.5 mg brexpiprazole on days 1-4 ordays 1-7 (depending on the patient's condition). In some embodiments, apatient is administered a total daily dose of 1 mg brexpiprazole on days1-4 or days 1-7 (depending on the patient's condition). In someembodiments, a patient is administered a total daily dose of 1.5 mgbrexpiprazole on days 1-4 or days 1-7 (depending on the patient'scondition). In some embodiments, a patient is administered a total dailydose of 2 mg brexpiprazole on days 1-4 or days 1-7 (depending on thepatient's condition).

In various embodiments, any of the starting doses described herein areadministered as two equal doses, twice per day (BID) for a definedperiod of time, e.g., for 1, 2, 3, 4, 5, 6, or 7 days, or anycombination or range thereof. In some embodiments, a patient isadministered 0.25 mg brexpiprazole twice daily on days 1-7. In someembodiments, a patient is administered 0.5 mg brexpiprazole twice dailybrexpiprazole on days 1-4 or days 1-7 (depending on the patient'scondition). In some embodiments, a patient is administered 0.75 mgbrexpiprazole twice daily brexpiprazole on days 1-4 or days 1-7(depending on the patient's condition). In some embodiments, a patientis administered 1 mg brexpiprazole twice daily on days 1-4 or days 1-7(depending on the patient's condition).

In some embodiments, the dose of brexpiprazole is increased from thestarting dose. In some embodiments, the dose of brexpiprazole isincreased every 2-3 days, every 3-4 days, every 4-5 days, or every 6-7days. In some embodiments, the dose of brexpiprazole is increased everyweek, every two weeks, every three weeks, or every month. In someembodiments, on day 5 of brexpiprazole administration, the dose ofbrexpiprazole is double that of the dose provided on the FDA label forday 5. In some embodiments, on day 8 of brexpiprazole administration,the dose of brexpiprazole is double that of the dose provided on the FDAlabel for day 8. In some embodiments, on day 15 of brexpiprazoleadministration, the dose of brexpiprazole is double that of the doseprovided on the FDA label for day 15.

In some embodiments, the dose of brexpiprazole is increased from thestarting dose by an amount ranging from about 0.25 mg to about 2 mg, forexample, about 0.25 mg, about 0.5 mg, about 1 mg, about 1.5 mg, or about2 mg, including all values and ranges in between. In some embodiments,the dose of brexpiprazole is increased by an amount ranging from about0.25 mg to about 6 mg, for example, about 0.5 mg, about 1 mg, about 1.5mg, about 2 mg, about 2.5 mg, about 3 mg, about 3.5 mg, about 4 mg,about 4.5 mg, about 5 mg, about 5.5 mg, or about 6 mg, every 2-3 days,every 3-4 days, every 4-5 days, or every 6-7 days, including all valuesand ranges therebetween. In some embodiments, the dose of brexpiprazoleis increased by an amount ranging from about 0.5 mg to about 6 mg, forexample, about 0.5 mg, about 1 mg, about 1.5 mg, about 2 mg, about 2.5mg, about 3 mg, about 3.5 mg, about 4 mg, about 4.5 mg, about 5 mg,about 5.5 mg, or about 6 mg, every week, every two weeks, every threeweeks, or every month, including all values and ranges therebetween. Insome embodiments, on day 5 of brexpiprazole administration, the dose ofbrexpiprazole is doubled from the starting dose. In some embodiments, onday 8 of brexpiprazole administration, the dose of brexpiprazole isdoubled from the starting dose.

Schizophrenia

In some embodiments, an obese CYP2D6 EM patient or obese CYP2D6 PMpatient is administered a starting dose of 1 mg or 2 mg brexpiprazole asa total daily dose on days 1-4, according to the modified dosingregimens disclosed herein. In some embodiments, an obese CYP2D6 EMpatient or obese CYP2D6 PM patient is administered a starting dose of0.5 mg or 1 mg brexpiprazole, twice daily, on days 1-4, according to themodified dosing regimens disclosed herein.

In some embodiments, on day 5, the dose of brexpiprazole is increasedfrom the starting dose. In some embodiments, the dose of brexpiprazoleis increased on day 5 and maintained for the duration of brexpiprazoleuse. In some embodiments, the dose of brexpiprazole is increased on day5, and the increased dose is administered from days 5-7. In someembodiments, the total daily dose administered on days 5-7 is 2-4 mg (2mg, 2.5 mg, 3 mg, 3.5 mg, or 4 mg, inclusive of all values and rangestherebetween). In some embodiments, the dose administered on days 5-7 is1-2 mg (e.g., 1 mg, 1.5 mg, or 2 mg, inclusive of all values and rangestherebetween) brexpiprazole twice daily.

In some embodiments, the patient resumes administration of therecommended daily dose starting on day 8. In some embodiments, an obeseCYP2D6 EM patient or obese CYP2D6 PM patient is administered 2-4 mg (2mg, 2.5 mg, 3 mg, 3.5 mg, or 4 mg, inclusive of all values and rangestherebetween) on day 8.

In some embodiments, on day 8, the dose of brexpiprazole is increasedfrom the starting dose. In some embodiments, on day 8, the dose ofbrexpiprazole is increased from the dose administered on days 5-7. Insome embodiments, the dose of brexpiprazole is increased on day 8, fromthe starting dose or from the dose administered on days 5-7. In someembodiments, the dose of brexpiprazole is increased on day 8 andmaintained for the duration of brexpiprazole use. In some embodiments,the dose of brexpiprazole is increased on day 8, from the starting doseor from the dose administered on days 5-7, wherein the increase ismaintained for days 8-14 of brexpiprazole use. In some embodiments, thedose administered on days 8-14 is 1-4 mg (1 mg, 1.5 mg, 2 mg, 2.5 mg, 3mg, 3.5 mg, or 4 mg, inclusive of all values and ranges therebetween) asa total daily dose. In some embodiments, the dose administered on days8-14 is 1-2 mg (e.g., 1 mg, 1.5 mg, or 2 mg, inclusive of all values andranges therebetween) brexpiprazole twice daily.

In some embodiments, the patient resumes administration of therecommended daily dose starting on day 15. In some embodiments, an obeseCYP2D6 EM patient or obese CYP2D6 PM patient is administered 2-4 mg (2mg, 2.5 mg, 3 mg, 3.5 mg, or 4 mg, inclusive of all values and rangestherebetween) on day 15.

In some embodiments, a dose of about 0.5 mg to about 1 mg ofbrexpiprazole is administered twice daily on days 1-4, a dose of about 1mg to about 2 mg of brexpiprazole is administered twice daily on days5-7, and about 2 mg to about 4 mg of brexpiprazole is administered oncedaily or twice daily starting on day 8. In some embodiments, a dose ofabout 0.5 mg to about 1 mg of brexpiprazole is administered twice dailyon days 1-4, a dose of about 1 mg to about 2 mg of brexpiprazole isadministered twice daily on days 5-7, about 2 mg to about 4 mg ofbrexpiprazole is administered once daily or twice on days 8-15, andabout 2-4 mg brexpiprazole is administered once daily starting on day15. In some embodiments, a dose of about 0.5 mg brexpiprazole isadministered twice daily on days 1-4, a dose of about 1 mg ofbrexpiprazole is administered twice daily on days 5-7, about 2 mg ofbrexpiprazole is administered twice daily on days 8-15, and about 1-2 mgbrexpiprazole is administered once daily starting on day 15. In someembodiments, a dose of about 1 mg brexpiprazole is administered twicedaily on days 1-4, a dose of about 2 mg of brexpiprazole is administeredtwice daily on days 5-7, about 2-4 mg of brexpiprazole is administeredonce daily starting on day 8-15. In some embodiments, a dose of about0.5 mg brexpiprazole is administered twice daily on days 1-4, a dose ofabout 1 mg of brexpiprazole is administered twice daily on days 5-7,about 1-2 mg of brexpiprazole is administered once daily starting on day8. In some embodiments, a dose of about 1 mg brexpiprazole isadministered twice daily on days 1-4, a dose of about 2 mg ofbrexpiprazole is administered twice daily on days 5-7, about 2-4 mg ofbrexpiprazole is once daily starting on day 8.

In some embodiments, a total daily dose of about 1 mg to about 2 mg ofbrexpiprazole is administered on days 1-4, a total daily dose of about 2mg to about 4 mg of brexpiprazole is administered on days 5-7, and atotal daily dose of between about 2-4 mg of brexpiprazole isadministered starting on day 8.

In some embodiments, the dose of brexpiprazole is increased from thestarting dose on day 5 and maintained for days 5-7, and then decreasedto the recommended daily dose on day 8 for the duration of brexpiprazoleuse. In some embodiments, the dose of brexpiprazole is increased fromthe starting dose on day 5 and maintained for days 5-7, then increasedagain on day 8 and maintained from days 8-14, and decreased to therecommended daily dose on day 15 for the duration of brexpiprazole use.In some embodiments, the dose administered on day 15 is 1 mg, 2 mg, 3mg, or 4 mg.

In some embodiments, the patient with schizophrenia is an obese patientwho is not a CYP2D6 poor metabolizer (in other words, the patient is anobese CYP2D6 EM patient), and the method comprises: (a) administering 1mg brexpiprazole twice daily on each of the first 4 days ofbrexpiprazole treatment; (b) administering 2 mg brexpiprazole twicedaily on each of the next 3 days following step (a); and then (c)administering a recommended dose of brexpiprazole (2-4 mg/day) oncedaily thereafter. In some embodiments, the patient with schizophrenia isan obese patient who is a CYP2D6 poor metabolizer, and the methodcomprises: (a) administering 0.5 mg brexpiprazole twice daily on each ofthe first 4 days of brexpiprazole treatment; (b) administering 1 mgbrexpiprazole twice daily on each of the next 3 days following step (a);and then (c) administering half of a recommended daily dose ofbrexpiprazole (e.g., 1-2 mg/day) once daily thereafter.

In some embodiments, a patient with schizophrenia is treated with amodified dosage regimen as found in Table 3. The dosage found in Table 3is the total daily dose of brexpiprazole. In some embodiments, the totaldaily dose is divided into two doses, for example, a patient that isadministered a total daily dose of 4 mg brexpiprazole may beadministered a first dose of 2 mg brexpiprazole and a second dose of 2mg brexpiprazole.

TABLE 3 Dosing Regimens for Schizophrenia Dosage CYP2D6 Regimen Days 1-4Days 5-7 Days 8-14 Days 15+ Weight Status FDA 1 mg (QD) 2 mg (QD) 2-4 mg(QD) 2-4 mg (QD) All EM Label FDA 0.5 mg (QD) 1 mg (QD) 1-2 mg (QD) 1-2mg (QD) All PM Label Modified 2 mg (1 mg BID) 4 mg (2 mg BID) 2-4 mg(QD) 2-4 mg (QD) Obese EM Dosing Regimen 1 Modified 1 mg (0.5 mg BID) 2mg (1 mg BID) 2-4 mg (1-2 mg BID) 1-2 mg (QD) Obese PM Dosing Regimen 2Modified 1 mg (0.5 mg BID) 2 mg (1 mg BID) 1-2 mg (QD) 1-2 mg (QD)Non-obese PM Dosing Regimen 3

Adjunctive Treatment of Major Depressive Disorder

In some embodiments, an obese CYP2D6 EM patient or obese CYP2D6 PMpatient is administered, as a starting daily dose, a total daily dose of0.5 mg, 1 mg or 2 mg brexpiprazole on days 1-7, according to themodified dosing regimens disclosed herein. In some embodiments, an obesepatient or obese CYP2D6 PM patient is administered a starting dose of0.25 mg, 0.5 mg, or 1 mg brexpiprazole twice daily on days 1-7,according to the modified dosing regimens disclosed herein

In some embodiments, on day 8, the dose of brexpiprazole is increasedfrom the starting dose. In some embodiments, the dose of brexpiprazoleis increased on day 8 and maintained for the duration of brexpiprazoleuse. In some embodiments, the dose of brexpiprazole is increased on day8, and the increased dose is administered from days 8-14. In someembodiments, the patient resumes administration of the recommended dailydose starting on day 8 or starting on day 15. In some embodiments, thetotal daily dose of brexpiprazole administered on days 8-14 is 1-4 mg(e.g., 1 mg, 1.5 mg, 2 mg, 2.5 mg, 3 mg, 3.5 mg, or 4 mg, inclusive ofall values and ranges therebetween). In some embodiments, 0.5-2 mg (0.5mg, 1 mg, 1.5 mg, or 2 mg, inclusive of all values and rangestherebetween) is administered twice daily on days 8-14.

In some embodiments, the dose of brexpiprazole is increased on day 15,from the dose administered on days 8-14 of brexpiprazole use. In someembodiments, the dose of brexpiprazole is increased on day 15 from thedose administered on days 8-14 and maintained for the duration ofbrexpiprazole use. In some embodiments, the dose of brexpiprazole isincreased on day 15 from the dose administered on days 8-14, and thedose is administered on days 15-21 of brexpiprazole treatment. In someembodiments, the total daily dose of brexpiprazole administered on days15-21 is 1-6 mg (e.g., 1 mg, 1.5 mg, 2 mg, 2.5 mg, 3 mg, 3.5 mg, 4 mg,4.5 mg, 5 mg, 5.5 mg, or 6 mg, inclusive of all values and rangestherebetween). In some embodiments, 0.5-3 mg (0.5 mg, 1 mg, 1.5 mg, 2mg, 2.5 mg, or 3 mg, inclusive of all values and ranges therebetween) isadministered twice daily on days 8-14.

In some embodiments, patients resume administration of the recommendeddaily dose starting on day 22.

In some embodiments, the dose of brexpiprazole is increased on day 8from the starting dose. In some embodiments, the dose administered onday 8 is double the starting dose administered on day 1. In someembodiments, the starting dose of brexpiprazole is 0.25 mg, 0.5 mg, 1mg, or 2 mg. In some embodiments, the dose of brexpiprazole administeredon days 8-14 is 0.5 mg, 1 mg, or 2 mg.

In some embodiments, the dose of brexpiprazole is increased from thestarting dose on day 8 and maintained for days 8-14, increased again onday 14 and maintained from days 14-21, and decreased to the recommendeddaily dose on day 22 for the duration of brexpiprazole use. In someembodiments, the dose of brexpiprazole administered on starting on day22 is 1 mg, 1.5 mg, 2 mg, or 3 mg.

In some embodiments, the dose of brexpiprazole is increased from thestarting dose on day 8 and maintained for days 8-14, and then decreasedto the recommended daily dose on day 15 for the duration ofbrexpiprazole use. In some embodiments, the dose of brexpiprazoleadministered on starting on day 15 is 1 mg, 1.5 mg, 2 mg, or 3 mg.

In some embodiments, a patient is administered a starting dose of 2 mgon days 1-7, a total daily dose of 4 mg on days 8-14, a total daily doseof 2-3 mg starting on day 15 and for the duration of brexpiprazole use.

In some embodiments, a total daily dose of about 0.5 mg to about 2 mg ofbrexpiprazole is administered on days 1-7, a total daily dose of about 1mg to about 4 mg of brexpiprazole is administered on days 8-14, and atotal daily dose of between about 1-6 of brexpiprazole is administeredstarting on day 15. In some embodiments, a total daily dose of about 0.5mg to about 1 mg of brexpiprazole is administered on days 1-7, a totaldaily dose of about 1 mg to about 2 mg of brexpiprazole is administeredon days 8-14, and a total daily dose of about 2-3 mg of brexpiprazole isadministered starting on day 15. In some embodiments, a total daily doseof about 0.5 mg of brexpiprazole is administered on days 1-7, a totaldaily dose of about 1 mg of brexpiprazole is administered on days 8-14,a total daily dose of about 2 mg is administered on days 14-21, and atotal daily dose of 2-3 mg is administered starting on day 22 and forthe duration of treatment. In some embodiments, a total daily dose ofabout 1 mg of brexpiprazole is administered on days 1-7, a total dailydose of about 1 mg of brexpiprazole is administered on days 8-14, atotal daily dose of between about 2 mg is administered on days 14-21,and a total daily dose of 2-3 mg is administered starting on day 22 andfor the duration of treatment. In some embodiments, a total daily doseof about 0.5 mg of brexpiprazole is administered on days 1-7, a totaldaily dose of about 1 mg of brexpiprazole is administered on days 8-14,a total daily dose of about 1-1.5 mg is administered on days 14-21, anda total daily dose of 1-1.5 mg is administered starting on day 22 andfor the duration of treatment.

In some embodiments, a dose of about 0.25 mg to about 1 mg ofbrexpiprazole is administered twice daily on days 1-7, a dose of about0.5 mg to about 4 mg of brexpiprazole is administered on days 8-14, andabout 1 mg to about 3 mg of brexpiprazole is administered starting onday 15. In some embodiments, a dose of about 0.25 mg to about 1 mg ofbrexpiprazole is administered twice daily on days 1-7, a dose of about0.5 mg to about 2 mg of brexpiprazole is administered twice daily ondays 8-14, about 1 mg to about 3 mg of brexpiprazole is administeredonce daily starting on day 15. In some embodiments, a dose of about 0.25mg to about 1 mg of brexpiprazole is administered twice daily on days1-7, a dose of about 0.5 mg to about 1 mg of brexpiprazole isadministered twice daily on days 8-14, a dose of about 1 mg to about 2mg of brexpiprazole is administered twice daily on days 14-21, and doseof about 1 mg to about 1.5 mg is administered starting on day 22.

In some embodiments, about 0.5 or 1 mg brexpiprazole is administeredtwice daily on days 1-7 days, and then an increased dose of about 1 mgto about 2 mg of brexpiprazole is administered twice daily on days 8-14,and then from about 1 mg to about 3 mg brexpiprazole is administeredonce daily starting on day 15. In some embodiments, about 0.5 mgbrexpiprazole is administered twice daily on days 1-7, about 1 mg ofbrexpiprazole is administered twice daily on days 8-14, and then about 2mg to about 3 mg is administered once daily starting on day 15. In someembodiments, about 1 mg brexpiprazole is administered twice daily ondays 1-7, about 2 mg of brexpiprazole is administered once daily on days8-14, and then about 2 mg to about 3 mg is administered once dailystarting on day 15.

In some embodiments, about 0.25 or 0.5 mg brexpiprazole is administeredtwice daily on days 1-7 of brexpiprazole treatment, an increased dose of0.5 mg or about 1 mg brexpiprazole is administered twice daily on days8-14, an increased dose of 1-1.5 mg brexpiprazole is administered twicedaily on days 15-21, and a dose from about 1 mg to about 1.5 mg isadministered starting on day 22. In some embodiments, about 0.25 mgbrexpiprazole is administered twice daily on days 1-7 of brexpiprazoletreatment, about 0.5 mg brexpiprazole is administered twice daily ondays 8-14, about 1 mg brexpiprazole is administered twice daily on days15-21, and about 1-1.5 mg brexpiprazole is administered once dailystarting on day 22. In some embodiments, about 0.5 mg brexpiprazole isadministered twice daily on days 1-7 of brexpiprazole treatment, about 1mg brexpiprazole is administered twice daily on days 8-14, about 1-1.5mg brexpiprazole is administered twice daily on days 15-21, and about1-1.5 mg brexpiprazole is administered once daily starting on day 22.

In some embodiments, the patient with MDD in an obese patient who is nota CYP2D6 poor metabolizer (in other words, the patient is an obeseCYP2D6 EM patient), and the method comprises: (a) administering either0.5 or 1 mg brexpiprazole twice daily on each of the first 7 days ofbrexpiprazole treatment; (b) administering double the individualbrexpiprazole dose of step (a) once daily on each of the next 7 daysfollowing step (a); and then (c) administering the recommended dailydose of brexpiprazole (e.g., 2-3 mg/day) once daily thereafter. In someembodiments, the patient with MDD is an obese patient who is a CYP2D6poor metabolizer (i.e., an obese CYP2D6 PM), and the method comprises:(a) administering 0.5 mg brexpiprazole twice daily on each of the first7 days of brexpiprazole treatment; (b) administering 1 mg twice daily oneach of the next 7 days following step (a); and then (c) administeringhalf of the recommended daily dose of brexpiprazole (1-1.5 mg/day) oncedaily thereafter. In some embodiments, the patient with MDD is an obesepatient who is a CYP2D6 poor metabolizer (i.e., an obese CYP2D6 PM), andthe method comprises (a) administering 0.25 mg brexpiprazole twice dailyon each of the first 7 days of brexpiprazole treatment; (b)administering 0.5 twice daily on each of next 7 days following step (a);(c) administering 1 mg daily twice on each of the next 7 days followingstep (b); and then (d) administering half of the recommended daily doseof brexpiprazole (1-1.5 mg/day) once daily thereafter;

In some embodiments, an obese CYP2D6 EM or obese CYP2D6 PM patient withMDD is treated with a modified dosage regimen as found in Table 4. Thedosage found in Table 4 is the total daily dose of brexpiprazole. Whereindicated, the total daily dose is divided into two doses.

TABLE 4 Dosing Regimens for MDD CYP2D6 Dosage Regimen Days 1-7 Days 8-14Days 15+ Weight Status FDA Label 0.5 mg (QD) 1 mg (QD) 2-3 mg (QD) AllEM FDA Label 1 mg (QD) 2 mg (QD) 2-3 mg (QD) All EM FDA Label 0.25 mg(QD) 0.5 mg (QD) 1-1.5 mg(QD) All PM FDA Label 0.5 mg (QD) 1 mg (QD)1-1.5 mg (QD) All PM Modified 0.5 mg (BID) 1 mg (QD) 2-3 mg (QD) ObeseEM Dosing Regimen A Modified 1 mg (BID) 2 mg (QD) 2-3 mg (QD) Obese EMDosing Regimen B Modified 0.25 mg (BID) 0.5 mg (BID) 1 mg (BID to ObesePM Dosing 21 days) Regimen C 1-1.5 mg (QD starting on day 22) Modified0.5 mg (BID) 1 mg (BID) 1-1.5 mg Obese PM Dosing (QD) Regimen D Modified0.25 mg (BID) 1 mg (QD) 1-1.5 mg Normal- PM Dosing (QD) weight Regimen EModified 0.5 mg (BID) 1 mg (QD) 1-1.5 mg Normal- PM Dosing (QD) weightRegimen FPatient Populations

Applicants have found that certain classes of patients, i.e., obesepatients and/or poor hepatic enzyme metabolizers (e.g., CYP2D6 PM),treated with brexpiprazole according to the instructions within thebrexpiprazole FDA label (revised March 2020), have substantially lowerplasma levels of brexpiprazole when initiating treatment withbrexpiprazole, exhibit a substantially longer elimination half-lives(t1/2) of brexpiprazole compared to those exhibited in “normal”patients, and have lower C_(min) values than those exhibited in “normal”patients. “Normal” patients are patients who do not exhibit the specificphysiological characteristics described herein such as BMI of at leastabout 35 kg/m², % IBW of at least about 150%, waist size greater thanabout 42 inches, % body fat greater than about 40%, % android body fatgreater than about 40%, % gynoid body fat greater than about 40%, totalbody fat greater than about 40 kg, optionally in combination withimpaired hepatic metabolizing enzyme function, e.g., intermediate orpoor CYP2D6 metabolizers. Initiating brexpiprazole treatment accordingto the methods of the disclosure raises the plasma levels ofbrexpiprazole more quickly to therapeutic levels, and thus increases theC_(min) values of brexpiprazole more rapidly to the therapeutic levelsobtained by normal patients dosed according to the regimen described inthe FDA-approved labels for brexpiprazole published prior to the presentinvention (e.g., the REXULTI® label dated March 2020).

In some embodiments, the methods of the disclosure are used to treat apatient that is obese. In some embodiments, an obese patient has variouscharacteristics of body fat status (BFS). The term “body fat status,”“body fat characteristics,” “obese status,” “obese characteristics,”“body habitus,” or other derivations or variations thereof refer to atleast seven characteristics (BMI, % IBW, waist size, % body fat, %android fat, % gynoid fat, and total body fat) as described herein. Insome embodiments, an obese patient can be classified using one or moreof the aforementioned BFS. In some embodiments, obese patients exhibitone or more of the following characteristics: BMI of at least about 35kg/m², % IBW of at least about 150%, waist size greater than about 42inches, % body fat greater than about 40%, % android body fat greaterthan about 40%, % gynoid body fat greater than about 40%, total body fatgreater than about 40 kg.

In some embodiments, the class of patients treated by the methods of thepresent disclosure have a body mass index (BMI; expressed in units ofkg/m² unless otherwise specified) of at least about 25, at least about26, at least about 27, at least about 28, at least about 29, at leastabout 30, at least about 31, at least about 32, at least about 33, atleast about 34, at least about 35, at least about 36, at least about 37,at least about 38, at least about 39, at least about 40, at least about41, at least about 42, at least about 43, at least about 44, at leastabout 45, at least about 46, at least about 47, at least about 48, atleast about 49, at least about 50, at least about 51, at least about 52,at least about 53, at least about 54, at least about 55, at least about56, at least about 57, at least about 58, at least about 59, at leastabout 60, at least about 61, at least about 62, at least about 63, atleast about 64, at least about 65, at least about 66, at least about 67,at least about 68, at least about 69, at least about 70, at least about71, at least about 72, at least about 73, at least about 74, at leastabout 75, at least about 76, at least about 77, at least about 78, atleast about 79, at least about 80, at least about 81, at least about 82,at least about 83, at least about 84, at least about 85, at least about86, at least about 87, at least about 88, at least about 89, at leastabout 90, at least about 91, at least about 92, at least about 93, atleast about 94, at least about 95, at least about 96, at least about 97,at least about 98, at least about 99, at least about 100, at least about101, at least about 102, at least about 103, at least about 104, atleast about 105, at least about 106, at least about 107, at least about108, at least about 109, at least about 110, at least about 111, atleast about 112, at least about 113, at least about 114, at least about115, at least about 116, at least about 117, at least about 118, atleast about 119, at least about 120, at least about 121, at least about122, at least about 123, at least about 124, at least about 125, atleast about 126, at least about 127, at least about 128, at least about129, at least about 130, at least about 131, at least about 132, atleast about 133, at least about 134, at least about 135, at least about136, at least about 137, at least about 138, at least about 139, atleast about 140, at least about 141, at least about 142, at least about143, at least about 144, at least about 145, at least about 146, atleast about 147, at least about 148, at least about 149, at least about150, at least about 151, at least about 152, at least about 153, atleast about 154, at least about 155, at least about 156, at least about157, at least about 158, at least about 159, at least about 160, atleast about 161, at least about 162, at least about 163, at least about164, at least about 165, at least about 166, at least about 167, atleast about 168, at least about 169, at least about 170, at least about171, at least about 172, at least about 173, at least about 174, atleast about 175, at least about 176, at least about 177, at least about178, at least about 179, at least about 180, at least about 181, atleast about 182, at least about 183, at least about 184, at least about185, at least about 186, at least about 187, at least about 188, atleast about 189, at least about 190, at least about 191, at least about192, at least about 193, at least about 194, at least about 195, atleast about 195, at least about 196, at least about 197, at least about198, at least about 199, at least about 200, at least about 201, atleast about 202, at least about 203, at least about 204, at least about205, at least about 206, at least about 207, at least about 208, atleast about 209, or at least about 210, inclusive of all ranges andsubranges therebetween, and any BMI described herein. In one embodiment,the patient has a body mass index (BMI) of at least about 35. In anotherembodiment, the patient has a body mass index (BMI) of at least about40. In another embodiment, the patient has a body mass index (BMI) of atleast 50.

In some embodiments, a patient treated according to the methods of thepresent invention has a BMI of at least about 25 to at least about 29.9,at least about 25.5 to at least about 29, at least about 26 to at leastabout 28.5, at least about 26.5 to at least about 28, or at least about27 to at least about 27.5, inclusive of all ranges and subrangestherebetween, and can be termed overweight or pre-obese. In someembodiments, a patient with a BMI of at least about 30 to at least about34.9, at least about 30.5 to at least about 34, at least about 31 to atleast about 33.5, at least about 31.5 to at least about 33, or at leastabout 32 to at least about 32.5, inclusive of all ranges and subrangestherebetween can be considered obese. In some embodiments, a patientwith a BMI of at least about 35 to at least about 39.9, at least about35.5 to at least about 39, at least about 36 to at least about 38.5, atleast about 36.5 to at least about 38, or at least about 37 to at leastabout 37.5, inclusive of all ranges and subranges therebetween, and anyBMI described herein, can be considered obese. In other embodiments, apatient treated by the methods of the present disclosure has a BMI of atleast about 35 or more, 40 or more, 50 or more, 60 or more, 70 or more,80 or more, 90 or more, 100 or more, 110 or more, 120 or more, 130 ormore, 140 or more, 150 or more, 160 or more, 170 or more, 180 or more,190 or more, 200 or more, or 210 or more, inclusive of all ranges andsubranges therebetween.

In some embodiments, the patient treated according to the methods of thepresent disclosure is a child or an adolescent with a BMI of at leastabout the 85th percentile to at least about 95th percentile, at leastabout the 86th percentile to at least about 94th percentile, at leastabout the 87th percentile to at least about 93th percentile, at leastabout the 88th percentile to at least about 92th percentile, at leastabout the 89th percentile to at least about 90th percentile, inclusiveof all ranges and subranges therebetween, can be considered overweightor pre-obese. In some embodiments, the patient is a patient with a BMIof at least about the 95th percentile, at least about 96th percentile,at least about the 97th percentile, at least about 98th percentile, atleast about 99th percentile, or at least about 100th percentile,inclusive of all ranges and subranges therebetween, and any BMIpercentile described herein, and can be considered obese. In oneembodiment, the patient is about 5 to about 19 years old or about 7 toabout 18 years old.

In some embodiments, the patient treated according to the methods of thepresent disclosure is a female patient in the first trimester throughthird trimester of a pregnancy and has a BMI of at least 25 to at leastabout 29.9, at least about 25.5 to at least about 29, at least about 26to at least about 28.5, at least about 26.5 to at least about 28, or atleast about 27 to at least about 27.5, inclusive of all ranges andsubranges therebetween, and can be considered overweight or pre-obese.In some embodiments, the patient is a female patient in the firsttrimester through third trimester of a pregnancy and has a BMI of atleast about 30 to at least about 34.9, at least about 30.5 to at leastabout 34, at least about 31 to at least about 33.5, at least about 31.5to at least about 33, or at least about 32 to at least about 32.5,inclusive of all ranges and subranges therebetween, and can beconsidered obese. In some embodiments, the patient treated according tothe methods of the present invention is a female patient in the firsttrimester through third trimester of a pregnancy and has a BMI of atleast about 35 to at least about 39.9, at least about 35.5 to at leastabout 39, at least about 36 to at least about 38.5, at least about 36.5to at least about 38, at least about 37 to at least about 37.5,inclusive of all ranges and subranges therebetween, and can beconsidered severely obese.

In some embodiments, methods of calculating BMI may include, but are notlimited to body weight in kilogram/(height in meters)², body weight inpounds/(height in inches)²]×703, and the like.

In some embodiments, the patient treated according to the methods of thepresent disclosure can alternatively be described as having a % idealbody weight (% IBW) of at least about 110%, at least about 111%, atleast about 112%, at least about 113%, at least about 114%, at leastabout 115%, at least about 116%, at least about 117%, at least about118%, at least about 119%, at least about 120%, at least about 121%, atleast about 122%, at least about 123%, at least about 124%, at leastabout 125%, at least about 126%, at least about 127%, at least about128%, at least about 129%, at least about 130%, at least about 131%, atleast about 132%, at least about 133%, at least about 134%, at leastabout 135%, at least about 136%, at least about 137%, at least about138%, at least about 139%, at least about 140%, at least about 141%, atleast about 142%, at least about 143%, at least about 144%, at leastabout 145%, at least about 146%, at least about 147%, at least about148%, at least about 149%, at least about 150%, at least about 151%, atleast about 152%, at least about 153%, at least about 154%, at leastabout 155%, at least about 156%, at least about 157%, at least about158%, at least about 159%, at least about 160%, at least about 161%, atleast about 162%, at least about 163%, at least about 164%, at leastabout 165%, at least about 166%, at least about 167%, at least about168%, at least about 169%, at least about 170%, at least about 171%, atleast about 172%, at least about 173%, at least about 174%, at leastabout 175%, at least about 176%, at least about 177%, at least about178%, at least about 179%, at least about 180%, at least about 181%, atleast about 182%, at least about 183%, at least about 184%, at leastabout 185%, at least about 186%, at least about 187%, at least about188%, at least about 189%, at least about 190%, at least about 191%, atleast about 192%, at least about 193%, at least about 194%, at leastabout 195%, at least about 196%, at least about 197%, at least about198%, at least about 199%, at least about 200%, at least about 201%, atleast about 202%, at least about 203%, at least about 204%, at leastabout 205%, at least about 206%, at least about 207%, at least about208%, at least about 209%, at least about 210%, at least about 211%, atleast about 212%, at least about 213%, at least about 214%, at leastabout 215%, at least about 216%, at least about 217%, at least about218%, at least about 219%, at least about 220%, at least about 221%, atleast about 222%, at least about 223%, at least about 224%, at leastabout 225%, at least about 226%, at least about 227%, at least about228%, at least about 229%, at least about 230%, at least about 231%, atleast about 232%, at least about 233%, at least about 234%, at leastabout 235%, at least about 236%, at least about 237%, at least about238%, at least about 239%, at least about 240%, at least about 241%, atleast about 242%, at least about 243%, at least about 244%, at leastabout 245%, at least about 246%, at least about 247%, at least about248%, at least about 249%, at least about 250%, at least about 251%, atleast about 252%, at least about 253%, at least about 254%, at leastabout 255%, at least about 256%, at least about 257%, at least about258%, at least about 259%, at least about 260%, at least about 261%, atleast about 262%, at least about 263%, at least about 264%, at leastabout 265%, at least about 266%, at least about 267%, at least about268%, at least about 269%, at least about 270%, at least about 271%, atleast about 272%, at least about 273%, at least about 274%, at leastabout 275%, at least about 276%, at least about 277%, at least about278%, at least about 279%, or at least about 280%, inclusive of allranges and subranges therebetween, and any % ideal body weight describedherein. In one embodiment, the patient has % ideal body weight (IBW) ofat least about 150%. In one embodiment, the patient has % ideal bodyweight (IBW) of at least about 250%. In other embodiment, the patienthas % IBW of at least 150% and can be considered obese.

In some embodiments, the patient treated according to the presentdisclosure can alternatively be described as having a waist size orwaist circumference greater than about 32, greater than about 33,greater than about 34, greater than about 35 inches, greater than about36, greater than about 37, greater than about 38, greater than about 39,greater than about 40, greater than about 41, greater than about 42,greater than about 43, greater than about 44, greater than about 45,greater than about 46, greater than about 47, greater than about 48,greater than about 49, greater than about 50, greater than about 51,greater than about 52, greater than about 53, greater than about 54,greater than about 55, greater than about 56, greater than about 57,greater than about 58, greater than about 59, greater than about 60inches, greater than about 61 inches, greater than about 62 inches,greater than about 63 inches, greater than about 64 inches, greater thanabout 65 inches, inclusive of all ranges and subranges therebetween, andany waist size or circumference described herein. In one embodiment, apatient having a waist size or waist circumference of about 42 inchescan be considered obese. In another embodiment, the patient has waistsize or waist circumference greater than about 48 inches. In otherembodiment, the patient has waist or waist circumference of at least 42inches.

In some embodiments, a patient treated according to the methods of thepresent disclosure has a % body fat greater than about 20%, greater thanabout 21%, greater than about 22%, greater than about 23%, greater thanabout 24%, greater than about 25%, greater than about 26%, greater thanabout 27%, greater than about 28%, greater than about 29%, greater thanabout 30%, greater than about 31%, greater than about 32%, greater thanabout 33%, greater than about 34%, greater than about 35%, greater thanabout 36%, greater than about 37%, greater than about 38%, greater thanabout 39%, greater than about 40%, greater than about 41%, greater thanabout 42%, greater than about 43%, greater than about 44%, greater thanabout 45%, greater than about 46%, greater than about 47%, greater thanabout 48%, greater than about 49%, or greater than about 50%, inclusiveof all ranges and subranges therebetween, and any % body fat describedherein. In one embodiment, the patient has a % body fat greater thanabout 40%. In one embodiment, the patient has a % body fat of at leastabout 50%. In another embodiment, a patient having a % body fat greaterthan about 40% can be considered obese. In some embodiments, methods ofcalculating % body fat can include, but are not limited to total bodyfat expressed as a percentage of total body weight. Other standards forobesity can be used. For example, the American Council on Exercisesuggests that an “average” percentage of body fat for women is about25-31%, and for men, about 18-24%, and for obese women, about 32% andhigher, and obese men, about 25% and higher.

In some embodiments, a patient treated according to the methods of thepresent disclosure has a % android body fat greater than about 30%,greater than about 31%, greater than about 32%, greater than about 33%,greater than about 34%, greater than about 35%, greater than about 36%,greater than about 37%, greater than about 38%, greater than about 39%,greater than about 40%, greater than about 41%, greater than about 42%,greater than about 43%, greater than about 44%, greater than about 45%,greater than about 46%, greater than about 47%, greater than about 48%,greater than about 49%, greater than about 50%, greater than about 51%,greater than about 52%, greater than about 53%, greater than about 54%,greater than about 55%, greater than about 56%, greater than about 57%,greater than about 58%, greater than about 59%, greater than about 60%,greater than about 61%, greater than about 62%, greater than about 63%,greater than about 64%, greater than about 65%, greater than about 66%,greater than about 67%, greater than about 68%, greater than about 69%,greater than about 70%, greater than about 71%, greater than about 72%,greater than about 73%, greater than about 74%, greater than about 75%,greater than about 76%, greater than about 77%, greater than about 78%,greater than about 79%, or greater than about 80%, inclusive of allranges and subranges therebetween, and any % android body fat describedherein. In one embodiment, a patient having a % android body fat greaterthan about 40% can be considered obese. In one embodiment, a patienthaving a % android body fat greater than about 50% can be consideredobese.

In some embodiments, a patient treated according to the methods of thepresent disclosure has a % android body fat of at least about 30%, atleast about 31%, at least about 32%, at least about 33%, at least about34%, at least about 35%, at least about 36%, at least about 37%, atleast about 38%, at least about 39%, at least about 40%, at least about41%, at least about 42%, at least about 43%, at least about 44%, atleast about 45%, at least about 46%, at least about 47%, at least about48%, at least about 49%, at least about 50%, at least about 51%, atleast about 52%, at least about 53%, at least about 54%, at least about55%, at least about 56%, at least about 57%, at least about 58%, atleast about 59%, at least about 60%, at least about 61%, at least about62%, at least about 63%, at least about 64%, at least about 65%, atleast about 66%, at least about 67%, at least about 68%, at least about69%, at least about 70%, at least about 71%, at least about 72%, atleast about 73%, at least about 74%, at least about 75%, at least about76%, at least about 77%, at least about 78%, at least about 79%, or atleast about 80%, inclusive of all ranges and subranges therebetween, and% android body fat described herein. In one embodiment, the patient has% android body fat of at least about 50%.

In some embodiments, a patient treated according to the methods of thepresent disclosure has a % gynoid body fat greater than about 30%,greater than about 31%, greater than about 32%, greater than about 33%,greater than about 34%, greater than about 35%, greater than about 36%,greater than about 37%, greater than about 38%, greater than about 39%,greater than about 40%, greater than about 41%, greater than about 42%,greater than about 43%, greater than about 44%, greater than about 45%,greater than about 46%, greater than about 47%, greater than about 48%,greater than about 49%, greater than about 50%, greater than about 51%,greater than about 52%, greater than about 53%, greater than about 54%,greater than about 55%, greater than about 56%, greater than about 57%,greater than about 58%, greater than about 59%, greater than about 60%,greater than about 61%, greater than about 62%, greater than about 63%,greater than about 64%, greater than about 65%, greater than about 66%,greater than about 67%, greater than about 68%, greater than about 69%,greater than about 70%, greater than about 71%, greater than about 72%,greater than about 73%, greater than about 74%, greater than about 75%,greater than about 76%, greater than about 77%, greater than about 78%,greater than about 79%, or greater than about 80%, inclusive of allranges and subranges therebetween, and any % gynoid body fat describedherein. In one embodiment, a patient having a % gynoid body fat greaterthan about 40% can be considered obese. In one embodiment, a patienthaving a % gynoid body fat greater than about 50% can be consideredobese.

In some embodiments, a patient treated according to the methods of thepresent disclosure has a total body fat content greater than about 30kg, greater than about 31 kg, greater than about 32 kg, greater thanabout 33 kg, greater than about 34 kg, greater than about 35 kg, greaterthan about 36 kg, greater than about 37 kg, greater than about 38 kg,greater than about 39 kg, greater than about 40 kg, greater than about41 kg, greater than about 42 kg, greater than about 43 kg, greater thanabout 44 kg, greater than about 45 kg, greater than about 46 kg, greaterthan about 47 kg, greater than about 48 kg, greater than about 49 kg,greater than about 50 kg, greater than about 51 kg, greater than about52 kg, greater than about 53 kg, greater than about 54 kg, greater thanabout 55 kg, greater than about 56 kg, greater than about 57 kg, greaterthan about 58 kg, greater than about 59 kg, greater than about 60 kg,greater than about 61 kg, greater than about 62 kg, greater than about63 kg, greater than about 64 kg, greater than about 65 kg, greater thanabout 66 kg, greater than about 67 kg, greater than about 68 kg, greaterthan about 69 kg, greater than about 70 kg, greater than about 71 kg,greater than about 72 kg, greater than about 73 kg, greater than about74 kg, greater than about 75 kg, greater than about 76 kg, greater thanabout 77 kg, greater than about 78 kg, greater than about 79 kg, greaterthan about 80 kg, greater than about 81 kg, greater than about 82 kg,greater than about 83 kg, greater than about 84 kg, greater than about85 kg, greater than about 86 kg, greater than about 87 kg, greater thanabout 88 kg, greater than about 89 kg, greater than about 90 kg, greaterthan about 91 kg, greater than about 92 kg, greater than about 93 kg,greater than about 94 kg, greater than about 95 kg, greater than about96 kg, greater than about 97 kg, greater than about 98 kg, greater thanabout 99 kg, greater than about 100 kg, at least 101 kg, at least 102kg, at least 103 kg, at least 104 kg, at least 105 kg, at least 106 kg,at least 107 kg, at least 108 kg, at least 109 kg, or at least 110 kg,inclusive of all ranges and subranges therebetween, and any total bodyfat described herein. In one embodiment, a patient having total body fatgreater than about 40 kg can be considered obese. In one embodiment, apatient having total body fat greater than about 50 kg can be consideredobese.

In other embodiments, obesity status of patients treated with themethods of the present disclosure can be measured by waist-to-hip ratio.In other embodiments, obesity status of patients can be measured byskinfold thickness. In other embodiments, obesity status of patients canbe measured by bioelectric impedance. In other embodiments, obesitystatus of patients can be measured by underwater weighing ordensitometry. In other embodiments, the obesity status of patients canbe measured by air-displacement plethysmography. In other embodiments,obesity status of patients can be measured by dilution method orhydrometry. In other embodiments, the obesity status of patients can bemeasured by dual energy X-ray absorptiometry. In other embodiments, theobesity status of patients can be measured by computerized tomographyand magnetic resonance imaging. In some embodiments, the obesity statuscan be defined by, but is not limited to adopting the clinicalstandards, conventional standards, and/or the standards published by theWorld Health Organization and Center of Disease Control (both of whichare herein incorporated by reference in their entireties for allpurposes) when using the methods described herein. For example, the WHOdefines an obese person as a person with a BMI of 30 or more, anoverweight person is one with a BMI equal to or more than 25 (to lessthan 30). Similarly, the CDC defines normal as a BMI of 18.5 to lessthan 25, 25.0 to less than 30 as overweight, and 30.0 or higher asobese. The CDC further subdivides obesity into 3 classes: Class 1, a BMIof 30 to less than 35; Class 2, a BMI of 35 to less than 40; and Class3, as a BMI of 40 or higher. The CDC sometimes refers to Class 3 obesityas “extreme” or “severe” obesity.

As used herein, the term “about” refers to an amount somewhat more orless than the stated parameter value, for example plus or minus five orten percent of the object that “about” modifies, or as one of skill inthe art would recognize from the context (e.g., approximately 50% of theinterval between values). The term “about” also includes the valuereferenced. For example, a BMI of about 40 includes 40, as well asvalues somewhat below or above 40.

In some embodiments, the patient treated by the methods of the presentdisclosure can be characterized by two or more of the physiologicalcharacteristics described herein. For example the patient can have a BMIof at least about 35 and can have a % IBW of at least 150%. In someembodiments, the patient can have a BMI of at least about 35 and canhave a waist size greater than about 42 inches. In some embodiments, thepatient can have a BMI of at least about 35 and can have a % body fatgreater than about 40%. In some embodiments, the patient can have a BMIof at least about 35 and can have a % android body fat greater thanabout 40%. In some embodiments, the patient can have a BMI of at leastabout 35 and can have a % gynoid body fat greater than about 40%. Insome embodiments, the patient can have a BMI of at least about 35 andcan have total body fat greater than about 40 kg. In various otherembodiments, the patient can have any combination of two or more of anyof the specific physiological parameters described herein.

In some embodiments, the patient can have three or more of thephysiological parameters described herein, for example a BMI of at leastabout 35, a % IBW of at least 150%, and waist size greater than about 42inches. In some embodiments, the patient can have a BMI of at leastabout 35, a % IBW of at least 150%, and a % body fat greater than about40%. In some embodiments, the patient can have a BMI of at least about35, a % IBW of at least 150%, and a android body fat greater than about40%. In some embodiments, the patient can have a BMI of at least about35, a % IBW of at least 150%, and a % gynoid body fat greater than about40%. In some embodiments, the patient can have a BMI of at least about35, a % IBW of at least 150%, and total body fat greater than about 40kg. In various other embodiments, the patient can have any combinationof three or more of any of the specific physiological parametersdescribed herein.

In some embodiments, the patient can have four or more of thephysiological parameters described herein, for example the patient canhave a BMI of at least about 35, a % IBW of at least 150%, waist sizegreater than about 42 inches, and a % body fat greater than about 40%.In some embodiments, the patient can have a BMI of at least about 35, a% IBW of at least 150%, waist size greater than about 42 inches, and a %android body fat greater than about 40%. In some embodiments, thepatient can have a BMI of at least about 35, a % IBW of at least 150%,waist size greater than about 42 inches, and a % gynoid body fat greaterthan about 40%. In some embodiments, the patient can have a BMI of atleast about 35, a % IBW of at least 150%, a waist size greater thanabout 42 inches, and total body fat greater than about 43 kg. In someembodiments, the patient can have a BMI of at least about 35, a % IBW ofat least 150%, a waist size greater than about 42 inches, a % body fatgreater than about 40%, and a % android body fat greater than about 40%.In some embodiments, the patient can have a BMI of at least about 35, a% IBW of at least 150%, a waist size greater than about 42 inches, a %body fat greater than about 40%, and a % gynoid body fat greater thanabout 40%. In some embodiments, the patient can have a BMI of at leastabout 35, a % IBW of at least 150%, a waist size greater than about 42inches, a % body fat greater than about 40%, and total body fat greaterthan about 40 kg. In some embodiments, the patient can have a BMI of atleast about 35, a % IBW of at least 150%, a waist size greater thanabout 42 inches, a % body fat greater than about 40%, a % android bodyfat greater than about 40%, in % gynoid body fat greater than about 40%,and total body fat greater than about 40 kg. In one embodiment, thepatient who has a BMI of at least about 35, in % IBW of at least 150%, awaist size greater than about 42 inches, and a % body fat greater thanabout 40%, a % android body fat greater than about 40%, a % gynoid bodyfat greater than about 40%, and total body fat greater than about 40 kg.In various other embodiments, the patient can have any combination ofany or all of the specific physiological parameters described herein.

In some embodiments, the patient can have a waist size greater thanabout 42 inches, a % body fat greater than about 40%, and a % androidbody fat greater than about 40%. In some embodiments, the patient canhave a waist size greater than about 42 inches, a % body fat greaterthan about 40%, and a % gynoid body fat greater than about 40%. In someembodiments, the patient can have a waist size greater than about 42inches, a % body fat greater than about 40%, and total body fat greaterthan about 40 kg.

In some embodiments, the patient can have a % body fat greater thanabout 40%, a % android body fat greater than about 40%, and a % gynoidbody fat greater than about 40%. In some embodiments, the patient canhave a % body fat greater than about 40%, a % android body fat greaterthan about 40%, and total body fat greater than about 40 kg. In someembodiments, the patient can have a % body fat greater than about 40%, a% gynoid body fat greater than about 40%, and total body fat greaterthan about 40 kg. In some embodiments, a % android body fat greater thanabout 40%, and a % gynoid body fat greater than about 40%, and totalbody fat greater than about 43 kg. In some embodiments, the patient canhave any combinations of obesity characteristics described herein.

In some embodiments, the methods of the disclosure are used to treat anormal-weight patient. As used herein, a normal-weight patient has a BMIbetween about 18 kg/m² and 25 kg/m². In some embodiments, normal-weightpatients do not exhibit one or more of the following characteristics:BMI of at least about 35 kg/m², % IBW of at least about 150%, waist sizegreater than about 42 inches, % body fat greater than about 40%, %android body fat greater than about 40%, % gynoid body fat greater thanabout 40%, total body fat greater than about 40 kg.

In some embodiments, the patient treated by the methods of the presentdisclosure can be an adult human. In other embodiments, the patient canbe a male human. In still other embodiments, the patient can be a femalehuman.

In some embodiments, the methods of the disclosure are utilized to treatpatients with various hepatic enzyme statuses. Brexpiprazole ismetabolized primarily through oxidation via P450 isozymes such asCYP2D6. Alternatively, brexpiprazole is metabolized through oxidationvia P450 isozymes such as CYP3A4/5, CYP2C9, CYP2C19, CYP2A6, CYP2C8, orCYP2B6. Each individual may have different activity levels of the P450isozymes to metabolize brexpiprazole. Categorizations of metabolizersmay include, but are not limited to allelic heterogeneity in the P450isozyme genes. For instance, the CYP2D6 gene can have allelicheterogeneity and its functionality (i.e., associated enzyme activity)can be categorized as full functionality, decreased functionality, andnon-functionality. Further, CYP2D6 genotype can be categorized based onits metabolic status by using the “gene dose” method and can have thefollowing scoring scale: (1) alleles with full functionality: a value of1, (2) alleles with reduced functionality: a value of 0.5, and (3)alleles with no functionality: a value of 0. Alternatively, in someembodiments, the CYP2D6 genotype can be tested by using targeted variantanalysis. In some embodiments, the CYP2D6 genotype can be tested byusing sequence analysis of select exons.

The “normal” or typical patient has 2 normally functioning CYP2D6alleles, and has full “normal” CYP2D6 enzyme functionality or activityand is referred to as an “extensive CYP2D6 metabolizer.” Patients withone non-functional CYP2D6 allele and one normally functioning allelehave reduced CYP2D6 enzyme function and are termed “intermediate CYP2D6metabolizers.” Patients with 2 non-functional CYP2D6 alleles have littleor no CYP2D6 functionality or activity and are termed “poor CYP2D6metabolizers” or alternatively “CYP2D6 poor metabolizers (PM).”

As used herein, the term “extensive CYP2D6 metabolizer” refers to aperson who may have a gene dose score for the CYP2D6 allele of 1.5 or 2and may have superior capabilities for metabolizing brexpiprazolecompared to his or her counterpart who is assigned as “intermediateCYP2D6 metabolizer” or “poor CYP2D6 metabolizer.” As used herein, theterm “intermediate CYP2D6 metabolizer” refers to a person who may have agene dose score for the CYP2D6 allele of 0.5 to 1 and may have superiorcapabilities for metabolizing brexpiprazole compared to his or hercounterpart who is assigned as “poor CYP2D6 metabolizer.” As usedherein, the term “poor CYP2D6 metabolizer” refers to a person who mayhave a gene dose score for the CYP2D6 allele of 0 and may have the leastcapabilities for metabolizing brexpiprazole compared to his or hercounterpart who is assigned as an “intermediate metabolizer” or an“extensive metabolizer.” In some embodiments, other suitable orconventional standards of categorizing CYP2D6 metabolizers may be used.

In some embodiments, the methods of the disclosure are used to treat aCYP2D6 poor metabolizer. In some embodiments, the methods of thedisclosure are used to treat a CYP2D6 extensive metabolizer. In someembodiments, the methods of the disclosure are used to treat a CYP2D6intermediate metabolizer.

In some embodiments, the methods of the disclosure are used to treat apatient that is an intermediate CYP2D6 metabolizer and has at least oneof the obesity characteristics described herein. In some embodiments,the methods of the disclosure are used to treat a patient that is a poorCYP2D6 metabolizer and has at least one of the obesity characteristicsdescribed herein. In some embodiments, the methods of the disclosure areused to treat a patient that is an extensive CYP2D6 metabolizer and hasat least one of the obesity characteristics described herein.

In some embodiments, the methods of the disclosure are utilized to treata patient that is a normal weight and is an intermediate CYP2D6metabolizer. In some embodiments, the methods of the disclosure areutilized to treat a patient that is a normal weight and is a poor CYP2D6metabolizer. In some embodiments, the methods of the disclosure areutilized to treat a patient that is a normal weight and is an extensiveCYP2D6 metabolizer.

In some embodiments, the methods of the disclosure are utilized to treata patient that has a BMI greater than 25 kg/m² but less than 35 kg/m²and is an intermediate CYP2D6 metabolizer. In some embodiments, themethods of the disclosure are utilized to treat a patient that has a BMIgreater than 25 kg/m² but less than 35 kg/m² and is a poor CYP2D6metabolizer. In some embodiments, the methods of the disclosure areutilized to treat a patient that has a BMI greater than 25 kg/m² butless than 35 kg/m² and is an extensive CYP2D6 metabolizer.

In some embodiments, the methods of the disclosure are used to treat apatient with a disease selected from major depressive disorder,schizophrenia, post-traumatic stress disorder, bipolar disorder, bipolardepression, acute mania, agitation associated with Alzheimer's disease,borderline personality disorder, attention deficit hyperactivitydisorder, autism, conduct disorder, oppositional defiant disorder, andcombinations thereof.

In some embodiments, the methods of the disclosure are used to treat apatient with major depressive disorder. In some embodiments, the methodsof the disclosure are used as an adjunctive therapy to treat a patientwith major depressive disorder. In some embodiments, the methods of thedisclosure are used to treat a patient with schizophrenia.

As used herein, “normal,” “normal-weight,” “reference,” or otherderivations or variations thereof refers to a non-obese state in aperson who can have at least one of the following characteristics: BMIless than about 35 kg/m², % IBW less than about 150%, waist size lessthan about 42, % body fat less than about 40%, % android body fat lessthan about 40%, % gynoid body fat less than about 40%, and total bodyfat less than about 40 kg. Unless otherwise modified “normalmetabolizer” also means an extensive CYP2D6 metabolizer.

Pharmacokinetics

In some embodiments, after administering between about 0.5 mg and about8 mg (e.g., 0.25 mg, 0.5 mg, 1.0 mg, 2.0 mg, 2.5 mg, 3.0 mg, 3.5 mg, 4.0mg, 5.0 mg, 6.0 mg, 7.5 mg, 8 mg) of brexpiprazole, the obese CYP2D6 PMor obese CYP2D6 EM patient treating according to the modified dosingregimens disclosed herein have a minimum observed plasma drugconcentration (C_(min)) between about 30 ng/mL and about 120 ng/mL. Insome embodiments, the C_(min) is between about 30 ng/mL and about 60ng/mL nine days after administration of the day 1 dose of brexpiprazole.In some embodiments, the C_(min) is between about 60 ng/mL and about 95ng/mL 16 days after administration of the day 1 dose of brexpiprazole.In some embodiments, the C_(min) is at least about 40.4 ng/mL. In someembodiments, the Gnu, is at least about 90.9 ng/mL. In some embodiments,the Gnu, is at least about 10.1 ng/mL. In some embodiments, the Gnu, isat least about 40.4 ng/mL on day 14 of brexpiprazole administration. Insome embodiments, the C_(min) is at least about 90.9 ng/mL on day 14 ofbrexpiprazole administration. In some embodiments, the C_(min) is atleast about 10.1 ng/mL on day 14 of brexpiprazole administration. Insome embodiments, the C_(min) is about 30 ng/mL, about 35 ng/mL, about40 ng/mL, about 45 ng/mL, about 50 ng/mL, about 55 ng/mL, about 60ng/mL, about 65 mg/mL, about 70 ng/mL, about 75 ng/mL, about 80 ng/mL,about 85 ng/mL, about 90 ng/mL, about 95 ng/mL, about 100 ng/mL, about105 ng/mL, about 110 ng/mL, about 115 ng/mL, about 120 ng/mL, about 125ng/mL, or about 130 ng/mL, including all ranges and values in between.In some embodiments, the Gnu, is between 80% and 125% of any of theaforementioned values or ranges between the aforementioned values.

In some embodiments, the time to reach Cmin is reduced after dosage ofbrexpiprazole according to a modified dosage regimen described herein ascompared to dosage according to the brexpiprazole (REXULTI®) FDA labeldated March 2020. Example 2 shows that the time to reach therapeuticconcentrations of brexpiprazole using the modified dosage regimen isreduced in the patient populations described herein as compared to thetime to reach Cmin using the brexpiprazole (REXULTI®) FDA Label. In someembodiments, the time to reach Cmin according to a modified dosageregimen is reduced by between about 1 day and about 35 days, forexample, at least about 1 day, 2 days, 3 days, 4 days, 5 days, 6 days, 7days, 8 days, 9 days, 10 days, 11 days, 12 days, 13 days, 14 days, 15days, 16 days, 17 days, 18 days, 19 days, 2 days, 21 days, 22 days, 23days, 24 days, 25 days, 26 days, 27 days, 28 days, 29 days, 30 days, 31days, 32 days, 33 days, 34 days, or at least about 35 days, includingall values and ranges there between as compared to dosage according tothe brexpiprazole (REXULTI®) FDA label.

In some embodiments, after administering between about 0.5 mg and about8 mg (e.g., 0.25 mg, 0.5 mg, 1.0 mg, 2.0 mg, 2.5 mg, 3.0 mg, 3.5 mg, 4.0mg, 5.0 mg, 6.0 mg, 7.5 mg, 8 mg) of brexpiprazole, the obese CYP2D6 PMpatient or obese CYP2D6 EM patient has a maximum observed plasma drugconcentration (C_(max)) between about 50 ng/mL and about 150 ng/mL. Insome embodiments, the C_(max) is between about 50 ng/mL and about 100ng/mL nine days after administration of the day 1 dose of brexpiprazole.In some embodiments, the Cmax is between about 80 ng/mL and about 150ng/mL 16 days after administration of the day 1 dose of brexpiprazole.In some embodiments, the C_(max) is about 50 ng/mL, about 55 ng/mL,about 60 ng/mL, about 65 mg/mL, about 70 ng/mL, about 75 ng/mL, about 80ng/mL, about 85 ng/mL, about 90 ng/mL, about 95 ng/mL, about 100 ng/mL,about 105 ng/mL, about 110 ng/mL, about 115 ng/mL, about 120 ng/mL,about 125 ng/mL, about 130 ng/mL, about 135 ng/mL, about 140 ng/mL,about 145 ng/mL, or about 150 ng/mL including all ranges and values inbetween. In some embodiments, the C_(max) is between 80% and 125% of anyof the aforementioned values or ranges between the aforementionedvalues.

In some embodiments, after administering between about 0.25 mg and about8 mg (e.g., 0.25 mg, 0.5 mg, 1.0 mg, 2.0 mg, 2.5 mg, 3.0 mg, 3.5 mg, 4.0mg, 5.0 mg, 6.0 mg, 7.5 mg, 8 mg,) of brexpiprazole, the obese CYP2D6 PMor obese CYP2D6 EM patient has an area under the concentration timecurve from day 0 to day 9 (AUC₉) between 1000 ng*hr/mL and 2000ng*hr/mL. In some embodiments, after administering between about 0.5 mgand about 10 mg, the patient has an AUC₉ of between 1500 ng*hr/mL and2000 ng*hr/mL. In some embodiments, the AUC₉ is about 1000 ng*hr/mL,about 1100 ng*hr/mL, about 1200 ng*hr/mL, about 1300 ng*hr/mL, about1400 ng*hr/mL, about 1500 ng*hr/mL, about 1600 ng*hr/mL, about 1700ng*hr/mL, about 1800 ng*hr/mL, about 1900 ng*hr/mL, or about 2000ng*hr/mL, including all ranges and values in between. In someembodiments, the AUC₉ is between 80% and 125% of the aforementionedvalues.

In some embodiments, after administering between about 0.25 mg and about8 mg (e.g., 0.25 mg, 0.5 mg, 1.0 mg, 2.0 mg, 2.5 mg, 3.0 mg, 3.5 mg, 4.0mg, 5.0 mg, 6.0 mg, 7.5 mg, 8 mg) of brexpiprazole, the obese CYP2D6 PMpatient or obese CYP2D6 EM patient has an area under the concentrationtime curve from day 0 to day 16 (AUC₁₆) between 1800 ng*hr/mL and 2600ng*hr/mL. In some embodiments, after administering between about 0.5 mgand about 10 mg, the patient has an AUC₁₆ between 2000 ng*hr/mL and 2600ng*hr/mL. In some embodiments, after administering between about 0.5 mgand about 10 mg, the patient has an AUC₁₆ between 2000 ng*hr/mL and 2300ng*hr/mL. In some embodiments, the AUC₁₆ is about about 1800 ng*hr/mL,about 1900 ng*hr/mL, about 2000 ng*hr/mL, about 2100 ng*hr/mL, about2200 ng*hr/mL, about 2300 ng*hr/mL, about 2400 ng*hr/mL, about 2500ng*hr/mL, or about 2600 ng*hr/mL, including all ranges and values inbetween. In some embodiments, the AUC₁₆ is between 80% and 125% of theaforementioned values.

All documents or patents cited herein are incorporated by reference intheir entireties for all purposes.

The following examples are offered by way of illustration and not by wayof limitation.

Example 1. Brexpiprazole Pharmacokinetics in Obese and Obese CYP2D6 PM

Brexpiprazole is an atypical antipsychotic indicated to treatschizophrenia and for use as an adjunctive therapy to antidepressantsfor the treatment of major depressive disorder. Brexpiprazole is knownto have a drug-drug interaction with CYP2D6 inhibitors, and dosereductions are recommended for patients that are cytochrome P450 CYP2D6poor metabolizers (PM) or patients taking concomitant CYP2D6 inhibitors.CYP2D6 EM patients metabolize brexpiprazole normally, whereas CYP2D6 PMpatients are believed to eliminate brexpiprazole more slowly. The FDAlabel of brexpiprazole (REXULTI®) advises that these patient populationstake half of the usual dose of brexpiprazole. Table A shows therecommended dosing schedule of brexpiprazole for treating schizophreniain patients that are CYP2D6 PM and CYP2D6 extensive metabolizers (EM).The brexpiprazole FDA label does not contain recommendations forbrexpiprazole dosage according to body size. Therefore, obese patients(as described herein) are treated according to the same dosing scheduleas EM or PM (depending on their CYP2D6 metabolizer status)

TABLE A Brexpiprazole Dosing for Schizophrenia According to FDA LabelCYP2D6 Days 1-4 Days 5-7 Days 8+ EM   1 mg QD 2 mg QD 2-4 mg QD PM 0.5mg QD 1 mg QD 1-2 mg QDPBPK Modeling of Patients Dosed with Brexpiprazole According to the FDALabel

Physiologically based pharmacokinetic (PBPK) modeling was used toestimate the pharmacokinetic parameters of brexpiprazole of thefollowing schizophrenia patient populations after administeringbrexpiprazole according to the FDA label (REXULTI® label dated March2020): obese (BMI>35 kg/m²), normal weight (BMI=18 kg/m²-25 kg/m²),CYP2D6 poor metabolizer (PM), and CYP2D6 extensive metabolizer (EM).Although the PBPK modeling was based on the dosing regimen forschizophrenia according to the FDA label (REXULTI®, March 2020),pharmacokinetic parameters are dose-dependent and expected to be similarin MDD.

In order to simulate brexpiprazole under various conditions, awhole-body PBPK model was constructed to capture the drug's kinetics inmajor tissues. Model tissue compartments included adipose, bone, brain,large intestine, small intestine, heart, kidney, liver, lung, muscle,spleen, stomach, and skin tissues, as well as venous and arterial bloodcompartments. In order to accurately capture first-pass clearanceeffects on the drug, the model also included correct representation ofthe gastrointestinal tract organs and the liver. Additionally, aperipheral sampling site compartment was used to represent thePK-sampled venous blood concentration as it was found to more accuratelycapture referenced plasma concentrations. Drug distribution into eachtissue compartment was modeled assuming perfusion-limited kinetics, withpartitioning into tissue described by a partition coefficient (Kp)estimated using methods described by Poulin and Theil (2002).Brexpiprazole-specific biochemical parameters such as the log ofoctanol:water partition coefficient (logP), negative log aciddissociation constant (pKa), fraction unbound in the plasma (f_(up)),blood:plasma concentration ratio (BP), and clearance were obtained fromliterature; additional physiochemical properties used to calculate Kpswere obtained via DrugBank. Absorption was modeled assuming simplefirst-order absorption, and clearance of brexpiprazole was assumed tooccur entirely in the liver (˜1% renal clearance). Based on theliterature it was assumed that 46.7% of brexpiprazole clearance is dueto CYP3A4, with the remaining clearance due to CYP2D6 (43.3%) and otherroutes (10%). The impact of CYP2D6 PM status is known to decreasebaseline clearance by ˜30%, which was reflected in the reduced baselineclearance parameters due to CYP2D6 in PM simulations. Simulations werecarried out in a virtual population of 500 normal-weight and 500 obeseindividuals with age- and sex-specific physiological parameters (i.e.tissue flows and volumes) sampled from the National Health and NutritionExamination Survey (NHANES) dataset.

Model parameters were calibrated and subsequently qualified bydigitizing PK data from available literature and comparing predicted vs.observed AUC_(0-∞), C_(max), and time to C_(max) (T_(max)) under variousdose strengths, dosing scenarios (i.e., single dose vs. multiple dose),and routes of administration (i.e., intravenous or oral formulations).Calibration and qualification simulations were carried out using asingle typical individual (male, age=30 years, weight=73 kg, andheight=1.76 m). All comparisons yielded a geometric mean fold error lessthan or equal to 2, and thus were considered accurate for thesepurposes.

The Applicant's model was validated and shown to accurately predictobserved and literature pharmacokinetic parameters as shown in Tables Band C, below.

TABLE B Model Validation AUC (ng · h/mL) Cmax (ng/mL) Tmax (h) ReferenceRoute Dose (mg) Observed Predicted GMFE Observed Predicted GMFE ObservedPredicted GMFE Calibration NDA Study1 IV 0.25 172 175 1.02 4.73 5.071.07 1 1 1.0 Yes PO 2 1690 1350 1.25 22.10 19.5 1.13 6 4 1.5 Yes NDAStudy2 PO 0.2 123 135 1.10 2.62 1.95 1.35 2 4 2.0 No PO 0.5 287 337 1.176.64 4.87 1.36 4 4 1.0 No PO 1 636 675 1.06 11.70 9.74 1.20 6 4 1.5 NoPO 2 2160 1350 1.60 24.60 19.50 1.27 4 4 1.0 No PO 4 2760 2700 2.0047.20 38.90 1.21 6 4 1.5 No PO 6 5230 4050 1.29 71.10 58.40 1.22 6 4 1.5No PO 8 7920 5400 1.47 79.20 77.90 1.02 6 4 1.5 No GMFE = geometric meanfold error Calibration: Data used to optimize and/or refine PKparameters in the final model References are from NDA 205422 ClinicalPharmacology and Biopharmaceutics Review, p. 26 and 28

TABLE C Comparison to Literature CYP2D6 PM PK Values Brexpiprazole ModelComparisons AUC AUC GMR % Expected GMR Nor- O- Ex- Nor- O- Nor- O-Cohort Dose mal bese pected mal bese mal bese CYP2D6 4 mg 2703 2779 1.01.00 1.00 100% 100% EM CYP2D6 4 mg 4289 4397 1.5 1.59 1.58 106% 105% PMCYP2D6 2 mg 2134 2093 0.75 0.79 0.75 105% 100% PM “Expected” values arebased on population PK analysis in NDA 205422 Clinical Pharmacology andBiopharmaceutics Review

The modeling data showed that patients that are obese and obese CYP2D6PM take significantly longer to reach therapeutic plasma levels ofbrexpiprazole when initiating brexpiprazole treatment (Table D, and FIG.2A). This is based, at least in part, on Applicant's surprisingdiscovery that the half-life of brexpiprazole is dependent on both bodysize and CYP2D6 metabolizer status. Normal-weight CYP2D6 EM exhibit alower mean half-life than patients that are obese and/or CYP2D6 PM(Table D).

TABLE D Half-Life of Brexpiprazole in Different Patient PopulationsWeight CYP2D6 Mean half-life (SD), hours Normal EM 68.6 (45.0) Obese EM192 (130) Normal PM  107 (71.3) Obese PM 297 (207)

Additionally, obese and obese CYP2D6 PM patients take longer to reachsteady state plasma levels and therapeutic concentrations compared tonormal weight CYP2D6 EM when dosed using the instructions on the FDAlabel (Table E where EC50, EC80, and EC90 correspond to the plasmaconcentration at with 50%, 80%, or 90% of the population is expected torespond to treatment, respectively). Consequently, these patients takesignificantly longer to be treated than previously known, and somepatients may not actually reach therapeutic brexpiprazoleconcentrations. Thus, obese and CYP2D6 PM schizophrenia patients dosedaccording to the FDA label (e.g., REXULTI® label dated March 2020) arenot effectively treated. Ineffective schizophrenia treatment results insevere complications, including suicide attempts, anxiety, depression,alcohol or drug abuse, inability to work or attend school, financialproblems, homelessness, social isolation, health and medical problems,being victimized, and aggressive behavior.

TABLE E Pharmacokinetics Based on Current FDA Label Days to ReachPharmacokinetic Endpoints Weight CYP2D6 EC50 EC80 Steady State Normal EM3 9 21 Obese EM 6 11 37 Normal PM 5 10 24 Obese PM 7 15 46

Example 2. Schizophrenia

PBPK Modeling of Schizophrenia Patients Treated with Higher DosesAccording to Modified Methods

A modified dosing regimen was developed so that obese and CYP2D6 PMpatients reach therapeutic levels earlier (Table F). The modified dosageregimen for obese CYP2D6 EM and normal-weight CYP2D6 PM comprisesdoubling the total daily dose of brexpiprazole for days 1-7 of thedosage regimen. On day 8, patients returned to administering therecommended dose once daily. The modified dosage regimen for obeseCYP2D6 PM comprises doubling the total daily dose of brexpiprazole fordays 1-14 of the dosage regimen. On day 15, patients returned toadministering the recommended dose once daily. In contrast to themodified dosage regimen for obese CYP2D6 PM described herein whichdoubles the total daily brexpiprazole dosage for days 1-14, thebrexpiprazole FDA label recommends decreasing the total dailybrexpiprazole dosage by one-half in these patients.

TABLE F Modified Schizophrenia Dosing Regimens Weight CYP2D6 Days 1-4Days 5-7 Days 8-14 Days 15+ All EM 1 mg QD 2 mg QD 4 mg QD 4 mg QD(Label) (1 mg total (2 mg total (4 mg total (4 mg total daily dose)daily dose) daily dose) daily dose) Obese EM 1 mg BID 2 mg BID 4 mg QD 4mg QD (Modified (2 mg total (4 mg total (4 mg total (4 mg total Dosingdaily dose) daily dose) daily dose) daily dose) Regimen 1) All PM 0.5 mgQD 1 mg QD 2 mg QD 2 mg QD (Label) (0.5 mg total (1 mg total (2 mg total(2 mg total daily dose) daily dose) daily dose) daily dose) Obese PM 0.5mg BID 1 mg BID 2 mg BID 2 mg QD (Modified (1 mg total (2 mg total (4 mgtotal (2 mg total Dosing daily dose) daily dose) daily dose) daily dose)Regimen 2) Non- PM 0.5 mg BID 1 mg BID 1-2 mg 1-2 mg Obese (1 mg total(2 mg total (QD) (QD) (Modified daily dose) daily dose) Dosing Regimen3)

PBPK modeling shows that the pharmacokinetic parameters of obese CYP2D6PM and obese CYP2D6 EM schizophrenia patients treated with the modifieddosage regimen of Table F approach those of normal-weight CYP2D6 EM(Table I).

FIG. 3 shows that obese CYP2D6 EM schizophrenia patients that aretreated according to Modified Dosing Regimen 1 have plasma brexpiprazoleconcentrations that are similar to normal-weight CYP2D6 EM patients.Obese CYP2D6 EM patients that are administered twice the starting andrecommended daily doses for the first 7 days reach therapeuticconcentrations three days faster than obese CYP2D6 EM patients that areadministered brexpiprazole according to the FDA label (Table H).

FIG. 4 shows that obese CYP2D6 PM schizophrenia patients that aretreated according to Modified Dosing Regimen 2 reach therapeuticconcentration in a similar time to normal-weight CYP2D6 EM patients.Obese CYP2D6 PM schizophrenia patients that are administeredbrexpiprazole at twice the starting and recommended daily doses for thefirst 14 days reach therapeutic brexpiprazole concentrations five daysfaster than once daily dosing (Table H).

FIG. 5 shows that normal-weight CYP2D6 PM schizophrenia patients thatare administered brexpiprazole according to Modified Dosing Regimen 3reach therapeutic concentrations three days faster than once dailydosing.

Table G shows that the modified dosage regimen of Table F decreases thetime required for schizophrenia patients that are CYP2D6 PM and/or obeseto reach therapeutic concentrations. The modified dosage regimen bringsthe time required for obese CYP2D6 PM, normal-weight CYP2D6 PM, andobese CYP2D6 EM patients to reach therapeutic concentrations closer tothat of normal-weight CYP2D6 EM patients.

Table I shows a comparison between the area under the curve, maximalplasma concentration (C_(max)), and minimal plasma concentration(C_(min)) between schizophrenia patients dosed according to the FDAlabel and schizophrenia patients dosed according to the modified dosageregimen. The AUC, Cmax, and Cmin for obese CYP2D6 PM, obese CYP2D6 EM,and normal-weight CYP2D6 PM patients approach those of normal-weightCYP2D6 EM patients after treatment with the modified dosing regimen.

TABLE G Days to Reach Pharmacokinetic Endpoints using ModifiedBrexpiprazole Dosing Regimens of TABLE F Days of BID Steady WeightCYP2D6 dosing EC50 EC80 State Normal EM 0 3 9 21 Obese EM 7 3 8 33Normal PM 7 3 7 21 Obese PM 14 5 10 17

TABLE H Days Reduced to Reach Pharmacokinetic Endpoints After DosingAccording to Modified Dosing Regimen of TABLE F Steady Weight CYP2D6EC50 EC80 State Obese EM 3 3 −4 Obese PM 2 5 −29

TABLE I Pharmacokinetic Parameters Label Dosing Modified Dosing NormalNormal Obese Obese Normal Obese Obese EM PM EM PM PM EM PM Day 9 AUC1763 1073 1063 611 1554 1526 1166 (ng * hr/mL) Cmax 88.2 51.8 63.7 34.773.4 83.3 58.1 (ng/mL) Cmin 51.9 33.2 30.0 17.3 54.4 50.2 36.5 (ng/mL)Day 16 AUC 2600 1908 1967 1229 2008 2189 2147 (ng * hr/mL) Cmax 128.888.4 104.1 61.2 94.0 113.7 100.2 (ng/mL) Cmin 91.8 70.3 69.9 44.4 74.879.6 84.0 (ng/mL)

Example 3. Major Depressive Disorder (MDD)

PBPK Modeling of MDD Patients Treated with Higher Doses According toModified Methods

A modified dosing regimen was developed so that obese and CYP2D6 PMpatients reach therapeutic levels earlier (Table J). For obese CYP2D6EM, the modified dosage regimen comprises doubling the total daily doseof brexpiprazole for days 1-7 of the dosage regimen on the brexpiprazolelabel. On day 8, the patients are treated with the recommended dose oncedaily according to the brexpiprazole label. For obese CYP2D6 PM, themodified dosage regimen comprises doubling the total daily dose ofbrexpiprazole for days 1-14 or 1-21 (depending on the starting dose) ofthe dosage regimen. Thereafter (on day 15 or 22, depending on thestarting dose), the patients are treated with the recommended dose oncedaily according to the brexpiprazole label. In contrast to thesemodified dosage regimens for obese CYP2D6 PM (which doubles the totaldaily brexpiprazole dosage), the FDA label recommends decreasing thetotal daily brexpiprazole dosage by one-half in these patients.

TABLE J Modified MDD Dosing Regimens Weight CYP2D6 Days 1-7 Days 8-14Days 15-21 Days 21+ All (FDA EM 0.5 mg QD 1 mg QD (1 2 mg QD (2 2-3 mgQD Label) (0.5 mg total mg total daily mg total daily (2-3 mg dailydose) dose) dose) total daily dose) All EM 1.0 mg QD 2 mg QD (2 2-3 mgQD 2-3 mg QD (FDA Label) (1.0 mg total mg total daily (2-3 mg total (2-3mg daily dose) dose) daily dose) total daily dose) All (FDA PM 0.25 mgQD 0.5 mg QD 1.0 mg QD 1-1.5 mg Label) (0.25 mg total (0.5 mg total (1.0mg total QD (1-1.5 daily dose) daily dose) daily dose) mg total dailydose) All PM 0.5 mg QD 1 mg QD (1 1-1.5 mg QD 1-1.5 mg (FDA Label) (0.5mg total mg total daily (2 mg total QD (1-1.5 daily dose) dose) dailydose) mg total daily dose) Obese EM 0.5 mg BID 1 mg QD (1 2 mg QD (2 2-3mg QD (Modified (1 mg total mg total daily mg total daily (2-3 mg Dosingdaily dose) dose) dose) total daily Regimen A) dose) Obese EM 1 mg BID(2 2 mg QD (2 2-3 mg QD (2 2-3 mg QD (Modified mg total daily mg totaldaily mg total daily (2-3 mg Dosing dose) dose) dose) total dailyRegimen B) dose) Obese PM 0.25 mg BID 0.5 mg BID 1 mg BID (2 1 mg QD(Modified (0.5 mg total (1 mg total mg total daily Dosing daily dose)daily dose) dose) Regimen C) Obese PM 0.5 mg BID 1 mg BID (2 1 mg QD 1mg QD (Modified (1 mg total mg total daily Dosing daily dose) dose)Regimen D) Normal PM 0.25 mg BID 0.5 mg QD 1 mg QD 1-1.5 mg (Modified(0.5 mg total QD Dosing daily dose) Regimen E) Normal PM 0.5 mg BID 1 mgQD 1-1.5 mg QD 1-1.5 mg (Modified (1 mg total QD Dosing daily dose)Regimen F)

PBPK modeling shows that the pharmacokinetic parameters of obese CYP2D6PM and obese CYP2D6 EM schizophrenia patients treated with the modifieddosage regimen of Table J approach those of normal-weight CYP2D6 EM(Table K and Table L).

FIG. 6 shows the blood plasma profiles for obese CYP2D6 EM patients withMDD that are treated according to Modified Dosing Regimen A, and FIG. 7shows blood plasma profiles for obese patient that are treated accordingto Modified Dosing Regimen B. In both FIG. 6 and FIG. 7, starting on day8, the recommended dose was administered once daily.

FIG. 6 shows that obese CYP2D6 EM MDD patients that are treatedaccording to the Modified Dosing Regimen A (BID for the first 7 days andreturn to the recommended dose thereafter) have plasma brexpiprazoleconcentrations that are similar to normal-weight CYP2D6 EM patients.

FIG. 7 shows that obese CYP2D6 EM MDD patients that are treatedaccording to the Modified Dosing Regimen B (BID for the first 7 days andreturn to the recommended dose thereafter) have plasma brexpiprazoleconcentrations that are similar to normal-weight CYP2D6 EM patients.

FIG. 8 shows the blood plasma profiles for obese CYP2D6 PM patients withMDD that are treated according to Modified Dosing Regimen C, and FIG. 9shows blood plasma profiles for obese patients that are treatedaccording to Modified Dosing Regimen D. In FIG. 8, starting on day 22,half of the recommended dose was administered once daily. In FIG. 9,starting on day 15, half of the recommended dose was administered oncedaily.

FIG. 8 shows that obese CYP2D6 PM MDD patients that are treatedaccording to Modified Dosing Regimen C (BID for the first 21 days andreturn to half the recommended dose thereafter) reach therapeuticconcentrations in a similar time to normal-weight CYP2D6 EM patients.

FIG. 9 shows that obese CYP2D6 EM MDD patients that are treatedaccording to the Modified Dosing Regimen D (BID for the first 14 daysand return to half the recommended dose thereafter) have plasmabrexpiprazole concentrations that are similar to normal-weight CYP2D6 EMpatients.

FIG. 11 and FIG. 12 shows that normal-weight CYP2D6 PM MDD patients thatare administered brexpiprazole according to Modified Dosing Regimen Eand Modified Dosing Regimen F, respectively, reach therapeuticbrexpiprazole concentration in a similar time to normal-weight CYP2D6 EMpatients.

Table K shows a comparison between the area under the curve, maximalplasma concentration (C_(max)), and minimal plasma concentration(C_(min)) between MDD patients dosed according to the FDA label and MDDpatients dosed according to Modified Dosing Regimens A (starting dose of0.5 mg BID) and C (starting dose of 0.25 mg BID). The AUC, Cmax, andCmin for obese CYP2D6 PM, obese CYP2D6 EM, and normal-weight CYP2D6 PMpatients approach those of normal-weight CYP2D6 EM patients aftertreatment with the modified dosing regimen.

TABLE K Pharmacokinetic Parameters Modified Dosing Regimen with StartingDoses of 0.5 mg BID (Obese CYP2D6 EM) or 0.25 mg BID (Obese CYP2D6 PM)Label Dosing Modified Dosing Nor- Nor- O- O- Nor- O- O- mal mal besebese mal bese bese EM PM EM PM PM EM PM Day AUC 1271 924 965 938 9381011 1209 21 (ng * hr/mL) Cmax 63.3 43.1 51.4 30.6 44.0 53.3 54.8(ng/mL) Cmin 44.5 33.8 34.2 22.2 34.5 36.0 45.9 (ng/mL) Day AUC 13681052 1227 840 1057 1246 1160 30 (ng * hr/mL) Cmax 66.6 48.5 62.5 40.448.8 63.2 54.0 (ng/mL) Cmin 49.0 39.7 45.4 32.0 39.9 6.0 45.6 (ng/mL)

Table L shows a comparison between the area under the curve, maximalplasma concentration (C_(max)), and minimal plasma concentration(C_(min)) between MDD patients dosed according to the FDA label and MDDpatients dosed according to Modified Dosing Regimens B (starting dose of1 mg BID) and D (starting dose of 0. 5 mg BID). The AUC, Cmax, and Cminfor obese CYP2D6 PM, obese CYP2D6 EM, and normal-weight CYP2D6 PMpatients approach those of normal-weight CYP2D6 EM patients aftertreatment with the modified dosing regimen.

TABLE L Pharmacokinetic Parameters Modified Dosing Regimen with StartingDoses of 1 mg BID (Obese CYP2D6 EM) or 0.5 mg BID (Obese CYP2D6 PM)Label Dosing Modified Dosing Nor- Nor- O- O- Nor- O- O- mal mal besebese mal bese bese EM PM EM PM PM EM PM Day AUC 1361 1031 1178 776 10661253 1121 21 (ng * hr/mL) Cmax 66.4 47.7 59.9 37.7 49.2 63.5 52.2(ng/mL) Cmin 48.7 38.8 43.1 29.3 40.3 46.5 44.2 (ng/mL) Day AUC 13751081 1304 935 1088 1332 1112 30 (ng * hr/mL) Cmax 66.9 49.5 65.9 44.149.7 67.2 52.4 (ng/mL) Cmin 49.3 40.9 48.7 35.9 41.0 50.5 43.4 (ng/mL)

The invention claimed is:
 1. A method of initiating treatment ofschizophrenia with brexpiprazole in an obese patient who is not a CYP2D6poor metabolizer, comprising: (a) administering 1 mg brexpiprazole twicedaily on each of the first 4 days of brexpiprazole treatment; (b)administering 2 mg brexpiprazole twice daily on each of the next 3 daysfollowing step (a); and then (c) administering a recommended dose of 2-4mg/day brexpiprazole once daily thereafter; wherein the obese patienthas a BMI of at least about
 35. 2. The method of initiating treatment ofschizophrenia with brexpiprazole of claim 1, wherein the recommendeddose of brexpiprazole is 2 mg/day.
 3. The method of initiating treatmentof schizophrenia with brexpiprazole of claim 1, wherein the recommendeddose of brexpiprazole is 2.25 mg/day.
 4. The method of initiatingtreatment of schizophrenia with brexpiprazole of claim 1, wherein therecommended dose of brexpiprazole is 2.5 mg/day.
 5. The method ofinitiating treatment of schizophrenia with brexpiprazole of claim 1,wherein the recommended dose of brexpiprazole is 2.75 mg/day.
 6. Themethod of initiating treatment of schizophrenia with brexpiprazole ofclaim 1, wherein the recommended dose of brexpiprazole is 3 mg/day. 7.The method of initiating treatment of schizophrenia with brexpiprazoleof claim 1, wherein the recommended dose of brexpiprazole is 3.25mg/day.
 8. The method of initiating treatment of schizophrenia withbrexpiprazole of claim 1, wherein the recommended dose of brexpiprazoleis 3.5 mg/day.
 9. The method of initiating treatment of schizophreniawith brexpiprazole of claim 1, wherein the recommended dose ofbrexpiprazole is 3.75 mg/day.
 10. The method of initiating treatment ofschizophrenia with brexpiprazole of claim 1, wherein the recommendeddose of brexpiprazole is 4 mg/day.
 11. A method of initiating treatmentof schizophrenia with brexpiprazole in an obese patient who is a CYP2D6poor metabolizer, comprising: (a) administering 0.5 mg brexpiprazoletwice daily on each of the first 4 days of brexpiprazole treatment; (b)administering 1 mg brexpiprazole twice daily on each of the next 3 daysfollowing step (a); (c) administering 1-2 mg brexpiprazole twice dailyon each of the next 7 days; and then (d) administering 1-2 mg/day ofbrexpiprazole once daily thereafter; wherein the obese patient has a BMIof at least about
 35. 12. The method of initiating treatment ofschizophrenia with brexpiprazole of claim 11, wherein the dose ofbrexpiprazole administered in step (d) is 1 mg/day.
 13. The method ofinitiating treatment of schizophrenia with brexpiprazole of claim 11,wherein the dose of brexpiprazole administered in step (d) is 1.25mg/day.
 14. The method of initiating treatment of schizophrenia withbrexpiprazole of claim 11, wherein the dose of brexpiprazoleadministered in step (d) is 1.5 mg/day.
 15. The method of initiatingtreatment of schizophrenia with brexpiprazole of claim 11, wherein thedose of brexpiprazole administered in step (d) is 1.75 mg/day.
 16. Themethod of initiating treatment of schizophrenia with brexpiprazole ofclaim 11, wherein the dose of brexpiprazole administered in step (d) is2 mg/day.
 17. A method of initiating adjunctive treatment of majordepressive disorder with brexpiprazole in an obese patient who is not aCYP2D6 poor metabolizer, comprising: (a) administering either 0.5 or 1mg brexpiprazole twice daily on each of the first 7 days ofbrexpiprazole treatment; (b) administering double the individualbrexpiprazole dose of step (a) once daily on each of the next 7 daysfollowing step (a); and then (c) administering the recommended dailydose of brexpiprazole once daily thereafter; wherein the obese patienthas a BMI of at least about
 35. 18. The method of initiating adjunctivetreatment of major depressive disorder with brexpiprazole of claim 17,wherein step (a) is administering 0.5 mg brexpiprazole twice daily foreach of the first 7 days of brexpiprazole treatment, and step (b) isadministering 1 mg brexpiprazole once daily for each of the next 7 daysfollowing step (a).
 19. The method of initiating treatment of majordepressive disorder with brexpiprazole of claim 17, wherein step (a) isadministering 1 mg brexpiprazole twice daily for each of the first 7days of brexpiprazole treatment, and step (b) is administering 2 mgbrexpiprazole once daily for each of the next 7 days following step (a).20. The method of initiating treatment of major depressive disorder withbrexpiprazole of claim 17, wherein the recommended daily dose of step(c) is 2 mg/day.
 21. The method of initiating treatment of majordepressive disorder with brexpiprazole of claim 17, wherein therecommended daily dose of step (c) is 2.25 mg/day.
 22. The method ofinitiating treatment of major depressive disorder with brexpiprazole ofclaim 17, wherein the recommended daily dose of step (c) is 2.5 mg/day.23. The method of initiating treatment of major depressive disorder withbrexpiprazole of any of claim 1, wherein the recommended daily dose ofstep (c) is 2.75 mg/day.
 24. The method of initiating treatment of majordepressive disorder with brexpiprazole of any of claim 1, wherein therecommended daily dose of step (c) is 3 mg/day.
 25. A method ofinitiating adjunctive treatment of major depressive disorder withbrexpiprazole in an obese patient who is a CYP2D6 poor metabolizer,comprising: (a) administering 0.5 mg brexpiprazole twice daily on eachof the first 7 days of brexpiprazole treatment; (b) administering 1 mgtwice daily on each of the next 7 days following step (a); and then (c)administering 1-1.5 mg/day of brexpiprazole once daily thereafter;wherein the obese patient has a BMI of at least about
 35. 26. The methodof initiating treatment of major depressive disorder with brexpiprazoleof any of claim 9, wherein half of the recommended daily dose of step(c) is 1-1.5 mg/day.
 27. The method of initiating treatment of majordepressive disorder with brexpiprazole of any of claim 9, wherein halfof the recommended daily dose of step (c) is 1 mg/day.
 28. The method ofinitiating treatment of major depressive disorder with brexpiprazole ofany of claim 9, wherein half of the recommended daily dose of step (c)is 1.25 mg/day.
 29. The method of initiating treatment of majordepressive disorder with brexpiprazole of any of claim 9, wherein halfof the recommended daily dose of step (c) is 1.5 mg/day.